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Science with Brian Cox and Jeff Forshaw
L'universo quantistico svelato:
Con accattivante chiarezza e un entusiasmo contagioso gli autori, Brian Cox e Jeff Forshaw, si confrontano con la meccanica quantistica, una delle teorie fisiche più affascinanti, ma notoriamente ostica al grande pubblico. Semplicemente: cos’è la meccanica quantistica? Come si lega con le teorie di Newton e Einstein? E soprattutto, come facciamo a essere certi che sia una teoria valida? Il regno subatomico vanta una reputazione ambigua, sospesa tra la capacità di previsioni concrete e sbalorditive sul mondo che ci circonda, e la genesi di innumerevoli malintesi. Ne l’Universo quantistico svelato, Cox e Foshaw fanno piazza pulita di ogni confusione, offrendo un approccio illuminante e accessibile al mondo della meccanica quantistica, mostrando non solo cos’è e come funziona, ma anche perché è così importante.
304 pages, Kindle Edition
First published October 1, 2011
1074 people are currently reading
7919 people want to read
About the author
Brian Cox
103 books2,038 followersNot to be confused with actor [Author: Brian Cox].
Brian Edward Cox, OBE (born 3 March 1968) is a British particle physicist, a Royal Society University Research Fellow, PPARC Advanced Fellow and Professor at the University of Manchester. He is a member of the High Energy Physics group at the University of Manchester, and works on the ATLAS experiment at the Large Hadron Collider (LHC) at CERN, near Geneva, Switzerland. He is working on the R&D project of the FP420 experiment in an international collaboration to upgrade the ATLAS and the CMS experiment by installing additional, smaller detectors at a distance of 420 metres from the interaction points of the main experiments.
He is best known to the public as the presenter of a number of science programmes for the BBC, boosting the popularity of subjects such as astronomy; so is a science popularizer, and science communicator. He also had some fame in the 1990s as the keyboard player for the pop band D:Ream.
Brian Edward Cox, OBE (born 3 March 1968) is a British particle physicist, a Royal Society University Research Fellow, PPARC Advanced Fellow and Professor at the University of Manchester. He is a member of the High Energy Physics group at the University of Manchester, and works on the ATLAS experiment at the Large Hadron Collider (LHC) at CERN, near Geneva, Switzerland. He is working on the R&D project of the FP420 experiment in an international collaboration to upgrade the ATLAS and the CMS experiment by installing additional, smaller detectors at a distance of 420 metres from the interaction points of the main experiments.
He is best known to the public as the presenter of a number of science programmes for the BBC, boosting the popularity of subjects such as astronomy; so is a science popularizer, and science communicator. He also had some fame in the 1990s as the keyboard player for the pop band D:Ream.
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Displaying 1 - 30 of 380 reviews
February 27, 2012
Okay... well first off I should declare that I have a degree in Quantum Physics. And that I was bought this book as a present.
Its clearly trying to explain Quantum Theory for 'the layperson' - those that aren't scientists or mathematicians. That's a problem, because Quantum Theory is really rather complicated. In order to try and explain how wave addition works, the authors come up with what they obviously believe is a very straightforward mechanism to do with clocks. Only it takes them so long to explain the clock mechanism, that we've then forgotten what its for. And to be honest, I didn't understand the clocks thing anyway - and I do understand how wave addition works (so fortunately could skip this bit). But then they come back to it again and again.
And despite openly saying at the beginning, 'we're not going to use many equations in this book', they've clearly completely forgotten that by halfway through, or just realised its impossible to explain complicated Physics without them.
So in the end I struggled to understand everything they were talking about, in their efforts to 'dumb it down', but I suspect those efforts have failed too, because its probably more complicated to try and explain it simply than to explain it in your own language.
And if anyone really doesn't like Brian Cox (I was fairly neutral on him, but am put off a little now), I don't think you'll like this much... its definitely a wee bit smug. But the main problem is obviously that it ends up being inaccessible to virtually everyone.
Nice jacket though.
Its clearly trying to explain Quantum Theory for 'the layperson' - those that aren't scientists or mathematicians. That's a problem, because Quantum Theory is really rather complicated. In order to try and explain how wave addition works, the authors come up with what they obviously believe is a very straightforward mechanism to do with clocks. Only it takes them so long to explain the clock mechanism, that we've then forgotten what its for. And to be honest, I didn't understand the clocks thing anyway - and I do understand how wave addition works (so fortunately could skip this bit). But then they come back to it again and again.
And despite openly saying at the beginning, 'we're not going to use many equations in this book', they've clearly completely forgotten that by halfway through, or just realised its impossible to explain complicated Physics without them.
So in the end I struggled to understand everything they were talking about, in their efforts to 'dumb it down', but I suspect those efforts have failed too, because its probably more complicated to try and explain it simply than to explain it in your own language.
And if anyone really doesn't like Brian Cox (I was fairly neutral on him, but am put off a little now), I don't think you'll like this much... its definitely a wee bit smug. But the main problem is obviously that it ends up being inaccessible to virtually everyone.
Nice jacket though.
August 22, 2019
This book, irrespective of the complaints from other reviewers, still deserves 5 stars just for successfully deriving Heisenberg's Uncertainty correlation from first principles and moving on from there to explain Quantum theory without using complex mathematics. This book literally walks you through the approximate derivation of the The Chandrasekhar limit (the maximum mass a white dwarf star can have) beginning from classical concepts without solving a single partial differential equation of any order. It also stops to appreciate how such an incredible truth about the Universe can be divined from just sitting down with a paper and pencil and simply thinking.
I don't agree with the notion that the book is bad because it makes something obvious (like wave phase while calculating spatial probability density) complicated by doing the same with clocks. To me this is the only pop-science book I know where I have actually been intellectually taken through the development of a theory from first principles. Yes, knowing the maths that others invented for you over decades makes talking about QM easy NOW as you throw around Hamiltonians and probability densities. But what if you had to develop it from scratch as a physicist working in the 1900s? What would be your thinking process? How would you even begin to develop a theory such as this?
I think this book is special because it gives the lay reader a taste of how to THINK about QM from the basics. Once you get the concept, thinking of something as a clock or an amplitude or a spin or chicken-curry for that matter is trivial.
I don't agree with the notion that the book is bad because it makes something obvious (like wave phase while calculating spatial probability density) complicated by doing the same with clocks. To me this is the only pop-science book I know where I have actually been intellectually taken through the development of a theory from first principles. Yes, knowing the maths that others invented for you over decades makes talking about QM easy NOW as you throw around Hamiltonians and probability densities. But what if you had to develop it from scratch as a physicist working in the 1900s? What would be your thinking process? How would you even begin to develop a theory such as this?
I think this book is special because it gives the lay reader a taste of how to THINK about QM from the basics. Once you get the concept, thinking of something as a clock or an amplitude or a spin or chicken-curry for that matter is trivial.
June 12, 2012
If only they could stop with their stupid clocks and use standard terminology like 'amplitude'. Why complicate such a simple concept when there is ample stuff to simplify? Bad grades for that.
November 21, 2011
Brian Cox has picked up a lot of fans (and a few parodies) for his light and fluffy 'here's me standing on top of a mountain looking at the stars' TV science shows - no doubt a fair number of them will rush out and buy his latest collaboration with Jeff Forshaw. They will be disappointed. So, I suspect, will a number of My Little Pony fans, as with its rainbow cover and glittery lettering it only needs a pink pony tail bookmark to complete the look.
The reason The Quantum Universe will disappoint is not because it is a bad book. It's brilliant. But it is to Cox's TV show what the Texas Chainsaw Massacre is to Toy Story. It's a different beast altogether.
As they did with their E=mc2 book, but even more so here, Cox and Forshaw take no prisoners and are prepared to delve deep into really hard-to-grasp aspects of quantum physics. This is the kind of gritty popular science writing that makes A Brief History of Time look like easy-peasy bedtime reading - so it really isn't going to be for everyone, but for those who can keep going through a lot of hard mental work the rewards are great too.
More than anything, I wish this book had been available when I started my undergraduate course in physics. It would have been a superb primer to get the mind into the right way of thinking to deal with quantum physics. Using Feynman's least action/sum over paths with 'clocks' representing phase, the authors take us into the basics of quantum physics, effectively deriving Heisenberg's uncertainty principle from basic logic - wonderful.
They go on to describe electron orbitals, the mechanics of electronic devices, quantum electrodynamics, virtual particles in a vacuum and more with the same mix of heavy technical arguments, a little maths (though nowhere near as much as a physics textbook) and a lot of Feynman-style diagrams and logic.
The reason I think I would have benefited so much is that this book explains much more than an (certainly my) undergraduate course does. Not explaining why quantum physics does what it does - no one can do that. But explaining the powerful logic behind the science, laying the groundwork for the undergraduate to then be able to do the fancy maths and fling Hamiltonians around and such. It is very powerful in this respect and I would urge anyone about to start a physics degree (or in the early stages of one) to read it. I would also recommend it for someone who is just really interested in physics and is prepared to put a lot of work into reading it, probably revisiting some pages several times to get what Cox and Forshaw have in mind - because they don't ease up very often.
What I can't do, though, is recommend this as general popular science. It isn't the kind of excellent introduction that gives you an understanding of what's going on in quantum theory, a view of the mysteries and a broad understanding of what the topic is about. This book is just too hard core. I'd suggest that 90% plus of popular science readers shouldn't touch it with the proverbial barge pole. If that sounds condescending, it isn't meant to be. Good popular science can and does have a lot more content and thought provoking meat than a typical Brian Cox TV show - but this book goes so much further still than that, inevitably limiting its audience.
Review first published on www.popularscience.co.uk - reproduced with permission
The reason The Quantum Universe will disappoint is not because it is a bad book. It's brilliant. But it is to Cox's TV show what the Texas Chainsaw Massacre is to Toy Story. It's a different beast altogether.
As they did with their E=mc2 book, but even more so here, Cox and Forshaw take no prisoners and are prepared to delve deep into really hard-to-grasp aspects of quantum physics. This is the kind of gritty popular science writing that makes A Brief History of Time look like easy-peasy bedtime reading - so it really isn't going to be for everyone, but for those who can keep going through a lot of hard mental work the rewards are great too.
More than anything, I wish this book had been available when I started my undergraduate course in physics. It would have been a superb primer to get the mind into the right way of thinking to deal with quantum physics. Using Feynman's least action/sum over paths with 'clocks' representing phase, the authors take us into the basics of quantum physics, effectively deriving Heisenberg's uncertainty principle from basic logic - wonderful.
They go on to describe electron orbitals, the mechanics of electronic devices, quantum electrodynamics, virtual particles in a vacuum and more with the same mix of heavy technical arguments, a little maths (though nowhere near as much as a physics textbook) and a lot of Feynman-style diagrams and logic.
The reason I think I would have benefited so much is that this book explains much more than an (certainly my) undergraduate course does. Not explaining why quantum physics does what it does - no one can do that. But explaining the powerful logic behind the science, laying the groundwork for the undergraduate to then be able to do the fancy maths and fling Hamiltonians around and such. It is very powerful in this respect and I would urge anyone about to start a physics degree (or in the early stages of one) to read it. I would also recommend it for someone who is just really interested in physics and is prepared to put a lot of work into reading it, probably revisiting some pages several times to get what Cox and Forshaw have in mind - because they don't ease up very often.
What I can't do, though, is recommend this as general popular science. It isn't the kind of excellent introduction that gives you an understanding of what's going on in quantum theory, a view of the mysteries and a broad understanding of what the topic is about. This book is just too hard core. I'd suggest that 90% plus of popular science readers shouldn't touch it with the proverbial barge pole. If that sounds condescending, it isn't meant to be. Good popular science can and does have a lot more content and thought provoking meat than a typical Brian Cox TV show - but this book goes so much further still than that, inevitably limiting its audience.
Review first published on www.popularscience.co.uk - reproduced with permission
March 10, 2015
This book commits one of the cardinal sins of pop science, which is replacing mathematics (deemed by the authors to be too difficult for the apparently mentally deficient reader) with an analogy so tortured it ends up being far more complicated than it would have been if they had just used the damn math. As math goes, wave addition is actually pretty easy, so I have no idea why the authors thought that replacing waves with clocks and adding together the clocks was simpler. How can you add together clocks? How can a clock represent probability? Why would you use a clock when wave functions are far more easy to understand? Even if you assume that the average person is familiar with clocks and not with wave functions, they could have just spent two pages explaining wave addition instead of half the book explaining clock addition and saved us all some effort.
Read
March 14, 2012Simply put, I cannot really comment on this book. I didn't get most of it, but I couldn't tell you if this was more my problem, or the book's problem. Historically, I have been terrible with math. This book has just enough of it to leave me feeling lost more than 50% of the time. Even when I thought I understood something, that understanding was extremely tentative.
I have this sneaking suspicion that in trying to make a quantum physics book that is accessible to a layperson, while still including some mathematics (algebra, trigonometry, etc), they have written a book that is actually accessible to almost no one - too dumbed down for the math and physics types, and too much maths for the math-phobic types. But, once again, I cannot say this with a higher degree of certainty. It might have just been me.
I have this sneaking suspicion that in trying to make a quantum physics book that is accessible to a layperson, while still including some mathematics (algebra, trigonometry, etc), they have written a book that is actually accessible to almost no one - too dumbed down for the math and physics types, and too much maths for the math-phobic types. But, once again, I cannot say this with a higher degree of certainty. It might have just been me.
February 4, 2012
The Quantum Universe by Brian Cox & Jeff Forshaw
“The Quantum Universe" is the interesting book about the subatomic realm. Well known physicist and science celebrity Brian Cox along with fellow physicist Jeff Forshaw take us into the intimidating world of quantum mechanics. Using the latest in scientific understanding and creative analogies these scientists make complex topics accessible to the masses. This 272-page book is composed of the following eleven chapters: 1. Something Strange Is Afoot, 2. Being in Two Places at Once, 3. What Is a Particle? 4. Everything That Can Happen Does Happen, 5. Movement as an Illusion, 6. The Music of the Atoms, 7. The Universe in a Pin-head (and Why We Don’t Fall Through the Floor), 8. Interconnected, 9. The Modern World, 10. Interaction, and 11. Empty Space Isn’t Empty.
Positives:
1. The ability of great scientists to communicate to the masses.
2. Fascinating topic in the hands of experts. Well researched and well written.
3. Finally, a book about quantum mechanics that I can comprehend and in the process I didn’t perceive it was “dumbed” down either. Most importantly, it kept my interest and I learned while doing so. Bravo!
4. Great use of charts and illustrations to assist the reader. Many concepts of physics defy common logic so the choice of sound illustrations is a must in order to understand the concepts. As an example, the use of clocks to understand particles.
5. Grounding what we know based on the best knowledge that science can offer. The authors do a wonderful job of explaining the scientific process and defining what a good scientific theory is all about.
6. This is strictly a science book. The authors are focused on quantum mechanics, not on the supernatural. In fact, the term "God" or "Creator" was never articulated!
7. Effective use of math, math is vital in understanding physics but the authors know their target audience well and provide the math necessary to enhance the level of comprehension. The authors don’t make the mistake of other books that bombard readers with esoteric equations and don’t follow up with a comprehensive narration.
8. Great explanation of why the laws of quantum theory replace Newton’s laws.
9. The authors seamlessly capture discoveries and their discoverers throughout the book.
10. The unique characteristics of the electron, and I mean unique.
11. I'm in awe of science! It's truly amazing how a basic understanding of quantum theory can lead one to understand the observed properties of some of the most massive objects in the universe.
12. The great Richard Feynman and his contributions to quantum mechanics...the understanding of subatomic particles. "Feynman is a second Dirac, only this time human". A giant of the subatomic world.
13. Understanding that being counterintuitive (moving away from common experience) is common in quantum mechanics. In other words, embrace your weirdness.
14. Fascinating tidbits throughout such as it was often claimed that the youth of the scientists allowed them to free themselves of old ways of thinking and thus be able to understand the world of quantum theory. Of course there are exceptions...Schrodinger.
15. The probabilistic nature of quantum mechanics...the loss of predictive power, even Einstein was bothered with it.
16. The least action principle...a cornerstone of physics.
17. The Heisenberg's Uncertainty Principle...it's amazing how being annoyed by the attention that Schrodinger received would drive a great scientist to his own version of quantum theory. We are talking about great scientists, not reality-TV stars. Goes to show that even scientists are humans too.
18. The brief history of Planck's constant. He was able to explain the black body spectrum...the rest is well, history.
19. The fascinating result of how to describe a moving particle. The de Broglie equation and how it works and wave packets.
20. The vastness inside an atom and what exactly is going on inside there. If you like guitars or drums this section is for you. The term quantized is music to my ears.
21. The work of physicist Wolfgang Pauli and why we don't fall through the floor. The Pauli Exclusion Principle. Great stuff.
22. The book does touch up on cosmology and you know that is always fun.
23. The periodic table an interesting narrative.
24. Atomic clusters...chemical bonding, semiconductors.
25. An appreciation for one of the most important inventions ever, the transistor. Thank you quantum theory.
26. Profound thoughts and concepts: "Every electron in the Universe knows about the state of every other electron". And that goes for protons and neutrons too.
27. Understanding the utility of semiconductor materials. Who knew physics was so much fun?
28. The nature of interaction between particles. Quantum field theory and its rules.
29. Quantum electrodynamics (QED), the theory that explains how particles interact with each other and photons. Once again than you Mr. Feynman and Schwinger and company.
30. Anti-matter or an electron travelling backwards in time. Remember, embrace your weirdness. Oh and it does get weird.
31. A survey of The Standard Model of particle physics. Come on Large Hadron Collider (LHC)...
32. A list of all the known particles and if we are lucky with the aforementioned LHC certainly more will be added to the list.
33. How modern physics aim to provide an answer to "what is the origin of mass?" The key...the Higgs boson, come on LHC. Branching rules.
34. An interesting Epilogue on the death of Stars. Fascinating stuff, applied science at its best.
Negatives:
1. Quantum mechanics is complicated there is no ifs and buts about it. Even at the most accessible level some concepts will not be comprehended. Many concepts of physics defy common logic and so some patience is needed to go over some of the topics.
2. The metric system is used so those of us who are a product of the American system will suffer a minor discomfort. The truth is we should have embraced the metric system but that is a tale for another day.
3. No links to speak of other than to diagrams.
4. Further reading section would have been enhanced with a complete bibliography.
In summary, I thoroughly enjoyed reading this book. The authors made comprehending such complex topics fun which is an accomplishment in its own right. The introductory knowledge that I have obtained by this book helps me gain a better understanding of our world. My love of knowledge is rewarded by great books like The Quantum Universe”. We know so little about world but every little bit of knowledge that we do obtain through the endeavors of science just gives me a sense of awe that no other human experience can match. The quest for knowledge is the most fulfilling journey any human can take. Do yourself a favor and don’t hesitate to get the “The Quantum Universe”.
Further suggestions: "A Universe from Nothing" by Lawrence M. Krauss, "About Time" by Adam Frank, "Death from the Skies" by Philip Plait, "The Grand Design" by Stephen Hawking, and "The Age of Everything" by Mathew Hedman.
“The Quantum Universe" is the interesting book about the subatomic realm. Well known physicist and science celebrity Brian Cox along with fellow physicist Jeff Forshaw take us into the intimidating world of quantum mechanics. Using the latest in scientific understanding and creative analogies these scientists make complex topics accessible to the masses. This 272-page book is composed of the following eleven chapters: 1. Something Strange Is Afoot, 2. Being in Two Places at Once, 3. What Is a Particle? 4. Everything That Can Happen Does Happen, 5. Movement as an Illusion, 6. The Music of the Atoms, 7. The Universe in a Pin-head (and Why We Don’t Fall Through the Floor), 8. Interconnected, 9. The Modern World, 10. Interaction, and 11. Empty Space Isn’t Empty.
Positives:
1. The ability of great scientists to communicate to the masses.
2. Fascinating topic in the hands of experts. Well researched and well written.
3. Finally, a book about quantum mechanics that I can comprehend and in the process I didn’t perceive it was “dumbed” down either. Most importantly, it kept my interest and I learned while doing so. Bravo!
4. Great use of charts and illustrations to assist the reader. Many concepts of physics defy common logic so the choice of sound illustrations is a must in order to understand the concepts. As an example, the use of clocks to understand particles.
5. Grounding what we know based on the best knowledge that science can offer. The authors do a wonderful job of explaining the scientific process and defining what a good scientific theory is all about.
6. This is strictly a science book. The authors are focused on quantum mechanics, not on the supernatural. In fact, the term "God" or "Creator" was never articulated!
7. Effective use of math, math is vital in understanding physics but the authors know their target audience well and provide the math necessary to enhance the level of comprehension. The authors don’t make the mistake of other books that bombard readers with esoteric equations and don’t follow up with a comprehensive narration.
8. Great explanation of why the laws of quantum theory replace Newton’s laws.
9. The authors seamlessly capture discoveries and their discoverers throughout the book.
10. The unique characteristics of the electron, and I mean unique.
11. I'm in awe of science! It's truly amazing how a basic understanding of quantum theory can lead one to understand the observed properties of some of the most massive objects in the universe.
12. The great Richard Feynman and his contributions to quantum mechanics...the understanding of subatomic particles. "Feynman is a second Dirac, only this time human". A giant of the subatomic world.
13. Understanding that being counterintuitive (moving away from common experience) is common in quantum mechanics. In other words, embrace your weirdness.
14. Fascinating tidbits throughout such as it was often claimed that the youth of the scientists allowed them to free themselves of old ways of thinking and thus be able to understand the world of quantum theory. Of course there are exceptions...Schrodinger.
15. The probabilistic nature of quantum mechanics...the loss of predictive power, even Einstein was bothered with it.
16. The least action principle...a cornerstone of physics.
17. The Heisenberg's Uncertainty Principle...it's amazing how being annoyed by the attention that Schrodinger received would drive a great scientist to his own version of quantum theory. We are talking about great scientists, not reality-TV stars. Goes to show that even scientists are humans too.
18. The brief history of Planck's constant. He was able to explain the black body spectrum...the rest is well, history.
19. The fascinating result of how to describe a moving particle. The de Broglie equation and how it works and wave packets.
20. The vastness inside an atom and what exactly is going on inside there. If you like guitars or drums this section is for you. The term quantized is music to my ears.
21. The work of physicist Wolfgang Pauli and why we don't fall through the floor. The Pauli Exclusion Principle. Great stuff.
22. The book does touch up on cosmology and you know that is always fun.
23. The periodic table an interesting narrative.
24. Atomic clusters...chemical bonding, semiconductors.
25. An appreciation for one of the most important inventions ever, the transistor. Thank you quantum theory.
26. Profound thoughts and concepts: "Every electron in the Universe knows about the state of every other electron". And that goes for protons and neutrons too.
27. Understanding the utility of semiconductor materials. Who knew physics was so much fun?
28. The nature of interaction between particles. Quantum field theory and its rules.
29. Quantum electrodynamics (QED), the theory that explains how particles interact with each other and photons. Once again than you Mr. Feynman and Schwinger and company.
30. Anti-matter or an electron travelling backwards in time. Remember, embrace your weirdness. Oh and it does get weird.
31. A survey of The Standard Model of particle physics. Come on Large Hadron Collider (LHC)...
32. A list of all the known particles and if we are lucky with the aforementioned LHC certainly more will be added to the list.
33. How modern physics aim to provide an answer to "what is the origin of mass?" The key...the Higgs boson, come on LHC. Branching rules.
34. An interesting Epilogue on the death of Stars. Fascinating stuff, applied science at its best.
Negatives:
1. Quantum mechanics is complicated there is no ifs and buts about it. Even at the most accessible level some concepts will not be comprehended. Many concepts of physics defy common logic and so some patience is needed to go over some of the topics.
2. The metric system is used so those of us who are a product of the American system will suffer a minor discomfort. The truth is we should have embraced the metric system but that is a tale for another day.
3. No links to speak of other than to diagrams.
4. Further reading section would have been enhanced with a complete bibliography.
In summary, I thoroughly enjoyed reading this book. The authors made comprehending such complex topics fun which is an accomplishment in its own right. The introductory knowledge that I have obtained by this book helps me gain a better understanding of our world. My love of knowledge is rewarded by great books like The Quantum Universe”. We know so little about world but every little bit of knowledge that we do obtain through the endeavors of science just gives me a sense of awe that no other human experience can match. The quest for knowledge is the most fulfilling journey any human can take. Do yourself a favor and don’t hesitate to get the “The Quantum Universe”.
Further suggestions: "A Universe from Nothing" by Lawrence M. Krauss, "About Time" by Adam Frank, "Death from the Skies" by Philip Plait, "The Grand Design" by Stephen Hawking, and "The Age of Everything" by Mathew Hedman.
March 28, 2021
This book gives the real science behind the weird behaviour of the atoms and energy that make up we humans and the universe.
There's some difficult passages to read, mostly when the authors refer to winding clocks backwards and forwards, but in general I believe this book is pitched at a level where the majority of people have a chance of understanding what is being written about.
There are some very strange concepts to grasp: positrons that go backwards in time, electrons that are in two places at the same time, events that happen faster than the speed of light.
The most amazing fact is this:
The energy stored within one cubic metre of empty space as a result of quark and gluon condensation is a staggering 10 to the power 35 joules and the energy due to Higgs condensation is 100 times greater than this. That's the total amount of energy our sun produces in 1000 years. However, this is negative energy.
There's some difficult passages to read, mostly when the authors refer to winding clocks backwards and forwards, but in general I believe this book is pitched at a level where the majority of people have a chance of understanding what is being written about.
There are some very strange concepts to grasp: positrons that go backwards in time, electrons that are in two places at the same time, events that happen faster than the speed of light.
The most amazing fact is this:
The energy stored within one cubic metre of empty space as a result of quark and gluon condensation is a staggering 10 to the power 35 joules and the energy due to Higgs condensation is 100 times greater than this. That's the total amount of energy our sun produces in 1000 years. However, this is negative energy.
December 30, 2015
So what was the tipping point that caused me to read a popular book on Quantum Physics (QP) after years of successfully avoiding the topic ? It was running into this Webpost on Quantum Computing and it's video
http://nextbigfuture.com/2015/12/evol... .
This is less of a review and more of my idea and notes holding areas found on Quantum Physics. Sources material includes this book , Quantum Physics For Poets and others I may read over time. Also some video and web resources ( Nova Special recommended! : https://www.youtube.com/watch?v=CBrsW... ) .
A goal of mine is to determine what exactly are some of the identified weird qualities found in Quantum Physics and how we have learned about them. Enough so I can be conversational with some one knowledgeable on the topic.
____________________________________________________
Everything we call real is made of things that cannot be regarded as real. If quantum mechanics has not profoundly shocked you, you haven’t understood it yet.” – Niels Bohr
Weirdness
* a particle can be in multiple places at once
* a particle moves from one place to another by exploring the entire universe simultaneously ?! (Feynman's work ?)
* light behaves both as a wave and a particle (from double slit experiment)- Duality
Uncertainty and Measurement
* It is simply impossible to determine with certainty when an atom will decay
* quantum theory deals with probabilities rather that certainties (it is not deterministic )
* we can not predict what photon would go through a window and which will bounce back as reflection
* Heisenberg's uncertainty principle- the more we know about a particles location the less we know about it's momentum . (it's impossible to know both at the same time)
* the act of measurement introduces a disturbance (further double slit experiments)
* when observation device is on it acts like a particle in the double slit when off it acts like a wave.As if it doesn't want to be observed going through each slit at once
* A particle may appear anywhere in the universe (?! unsure why we think this)
* scientists proved that photons' behaviour is indeed not decided until they are measured.
http://www.nature.com/scitable/blog/p...
Quantum Entanglement
* Quantum entanglement occurs when pairs or groups of particles are generated or interact in ways such that the quantum state of each particle cannot be described independently—instead, a quantum state may be given for the system as a whole.
* this entangled action appears to be faster than the Speed of light.
* This quantum entanglement was labeled 'Spooky Action at a Distance' by Einstein
( see this source http://www.pbs.org/wgbh/nova/physics/... )
* Einstein arguement about QP weirdness was best capture by his statement. God does not throw dice .. to which Bohr once stated that Einstein should stop telling God what he cannot do.
* Bohr felt that entangled particles could be separated by galaxies.
* normally the electons in entangled pair spin in opposite directions -down vs up.
* A paradox pointed out in Al-khalili book- entangled pairs are forever entangled until they are observed.
Teleportation
* we teleport the quantum state of a particle t a far distant particle (not the original itself which is destroyed)
* teleporation was thought of due to the "no cloning therom " of wooster and Zurek where the quantum state can not be copied to another while the original particle state remain the same.
Quantum Tunneling and other weird movement
* Quantum tunnelling is where a particle tunnels through a barrier that it classically could not surmount. (?!)
*scanning tunneling microscopes are an example.
http://phys.org/news/2015-05-physicis...
* quantum leap -an abrupt transition of an electron, atom, or molecule from one quantum state to another, with the absorption or emission of a quantum. (as in switching electron levels in an atom)
Time Travel
time travel and separation of characteristics :
http://www.nature.com/scitable/blog/p...
Additional QP Weirdness
* atoms can't have the same energy level (not sure if this is a correct interpetation, implies a communication across all space ?????)
* many worlds theorum-there is a belief that all possiblities occur in different dimensions.
* there is an example of quantum going back in time. (? need to comprehend this)
* The Aharonov–Bohm effect - a nonlocal effect similar to entanglement. in a magnetic field confined to the inside of a cylinder. electrons on the outside can be impacted by this field although logically they shouldn't.
* Superposition- being in a number of states at the same time.....being in two places at once.
* All Higgs particle is believe to come from the big bang.
*
*
*
* although many of QP seem unreal the results have been applicable in practice.
_________________________
* different atoms emit unique spectrums of light when heated (the basis of spectrometry ) Bohr felt this was due to electrons changing orbits.
* Plancks constant is the conversion factor between the wavelength of light and the energy of it's associate quanta. ( all speaks to photons as particles)
*Bells Theorum- (in simplest form ) a thought experiment which lead to an actual expiriment. No physical theory of local hidden variables can ever reproduce all of the predictions of quantum mechanics. Disproving EPR Theorems.
* John Bell- set an experimental conclusion that would prove either Quantum Physics or EPR to be correct. This experiment was performed after Bells death by Clauser (clauser, hrrne and Shimony).
Clauser said that Richard Feynman threw him out of his office when he said he was going to work on this problem.
*by proving , Hidden variables are impossible within the framework of proved quantum mechanics . Einstein school proved
* Pauli Exclusion theorem- No two electrons can be put into the exact same quantum state of motion at the same time
* Particle- broad definition- something at a point that has mass.
* White Dwarfs can only grow so large and then they will implode. This theoretical result appears to be born out observation: no white dwarfs bigger than the theoretical maximum.
* Dirac Sea- the vacuum of space is completely filled with Electrons, occupying all the negative energy states --Dirac work correctly predicted the existence of antimatter-
* We use antimatter currently- PET Scanner creates antimatter - this antimatter particle the opposite of the electron is the positron.
*there is such a thing as triple entanglement.
* entangled particles with a beam splitter.
* Ginsin did an experiment with a 1Ok fiber optic run that showed information would have to travel at 10 milion times the speed of light if it were not truly " spooky action at a distance"
* Ginsin work may have practical applications in quantum encryption
*particle interferometers- can direct particles down different paths and observe them . some weirdness observed in experiments.
http://nextbigfuture.com/2015/12/evol... .
This is less of a review and more of my idea and notes holding areas found on Quantum Physics. Sources material includes this book , Quantum Physics For Poets and others I may read over time. Also some video and web resources ( Nova Special recommended! : https://www.youtube.com/watch?v=CBrsW... ) .
A goal of mine is to determine what exactly are some of the identified weird qualities found in Quantum Physics and how we have learned about them. Enough so I can be conversational with some one knowledgeable on the topic.
____________________________________________________
Everything we call real is made of things that cannot be regarded as real. If quantum mechanics has not profoundly shocked you, you haven’t understood it yet.” – Niels Bohr
Weirdness
* a particle can be in multiple places at once
* a particle moves from one place to another by exploring the entire universe simultaneously ?! (Feynman's work ?)
* light behaves both as a wave and a particle (from double slit experiment)- Duality
Uncertainty and Measurement
* It is simply impossible to determine with certainty when an atom will decay
* quantum theory deals with probabilities rather that certainties (it is not deterministic )
* we can not predict what photon would go through a window and which will bounce back as reflection
* Heisenberg's uncertainty principle- the more we know about a particles location the less we know about it's momentum . (it's impossible to know both at the same time)
* the act of measurement introduces a disturbance (further double slit experiments)
* when observation device is on it acts like a particle in the double slit when off it acts like a wave.As if it doesn't want to be observed going through each slit at once
* A particle may appear anywhere in the universe (?! unsure why we think this)
* scientists proved that photons' behaviour is indeed not decided until they are measured.
http://www.nature.com/scitable/blog/p...
Quantum Entanglement
* Quantum entanglement occurs when pairs or groups of particles are generated or interact in ways such that the quantum state of each particle cannot be described independently—instead, a quantum state may be given for the system as a whole.
* this entangled action appears to be faster than the Speed of light.
* This quantum entanglement was labeled 'Spooky Action at a Distance' by Einstein
( see this source http://www.pbs.org/wgbh/nova/physics/... )
* Einstein arguement about QP weirdness was best capture by his statement. God does not throw dice .. to which Bohr once stated that Einstein should stop telling God what he cannot do.
* Bohr felt that entangled particles could be separated by galaxies.
* normally the electons in entangled pair spin in opposite directions -down vs up.
* A paradox pointed out in Al-khalili book- entangled pairs are forever entangled until they are observed.
Teleportation
* we teleport the quantum state of a particle t a far distant particle (not the original itself which is destroyed)
* teleporation was thought of due to the "no cloning therom " of wooster and Zurek where the quantum state can not be copied to another while the original particle state remain the same.
Quantum Tunneling and other weird movement
* Quantum tunnelling is where a particle tunnels through a barrier that it classically could not surmount. (?!)
*scanning tunneling microscopes are an example.
http://phys.org/news/2015-05-physicis...
* quantum leap -an abrupt transition of an electron, atom, or molecule from one quantum state to another, with the absorption or emission of a quantum. (as in switching electron levels in an atom)
Time Travel
time travel and separation of characteristics :
http://www.nature.com/scitable/blog/p...
Additional QP Weirdness
* atoms can't have the same energy level (not sure if this is a correct interpetation, implies a communication across all space ?????)
* many worlds theorum-there is a belief that all possiblities occur in different dimensions.
* there is an example of quantum going back in time. (? need to comprehend this)
* The Aharonov–Bohm effect - a nonlocal effect similar to entanglement. in a magnetic field confined to the inside of a cylinder. electrons on the outside can be impacted by this field although logically they shouldn't.
* Superposition- being in a number of states at the same time.....being in two places at once.
* All Higgs particle is believe to come from the big bang.
*
*
*
* although many of QP seem unreal the results have been applicable in practice.
_________________________
* different atoms emit unique spectrums of light when heated (the basis of spectrometry ) Bohr felt this was due to electrons changing orbits.
* Plancks constant is the conversion factor between the wavelength of light and the energy of it's associate quanta. ( all speaks to photons as particles)
*Bells Theorum- (in simplest form ) a thought experiment which lead to an actual expiriment. No physical theory of local hidden variables can ever reproduce all of the predictions of quantum mechanics. Disproving EPR Theorems.
* John Bell- set an experimental conclusion that would prove either Quantum Physics or EPR to be correct. This experiment was performed after Bells death by Clauser (clauser, hrrne and Shimony).
Clauser said that Richard Feynman threw him out of his office when he said he was going to work on this problem.
*by proving , Hidden variables are impossible within the framework of proved quantum mechanics . Einstein school proved
* Pauli Exclusion theorem- No two electrons can be put into the exact same quantum state of motion at the same time
* Particle- broad definition- something at a point that has mass.
* White Dwarfs can only grow so large and then they will implode. This theoretical result appears to be born out observation: no white dwarfs bigger than the theoretical maximum.
* Dirac Sea- the vacuum of space is completely filled with Electrons, occupying all the negative energy states --Dirac work correctly predicted the existence of antimatter-
* We use antimatter currently- PET Scanner creates antimatter - this antimatter particle the opposite of the electron is the positron.
*there is such a thing as triple entanglement.
* entangled particles with a beam splitter.
* Ginsin did an experiment with a 1Ok fiber optic run that showed information would have to travel at 10 milion times the speed of light if it were not truly " spooky action at a distance"
* Ginsin work may have practical applications in quantum encryption
*particle interferometers- can direct particles down different paths and observe them . some weirdness observed in experiments.
March 27, 2016
I am, frankly, unsure how much of quantum physics can be conveyed meaningfully without a mathematical description of the subject. Brian and Jeff did a heroic job in keeping maths out of the discussion, and for the most part I think they still managed to deliver interesting insights into the nature of quantum physics. For example, the idea to replace complex numbers with clocks is actually quite clever, although I agree with most reviewers on this site that this device failed to make things easier to grasp.
Also, I am not sure the clock-idea is entirely original. The authors clearly start off following an approach to quantum physics inspired by Feynman path integrals (at least that is what I thought lay buried beneath the metaphor of carrying clocks through the universe) and Feynman himself uses stopwatches to aid understanding in his own account on QED. But they do not seem to be touching on a lot of modern stuff - I am not knowledgeable enough to know for sure, but it seemed to me that Brian and Jeff put forward a reasonably dated view of the subject. I believe QED was basically formulated in the 40s, and (unless I missed it) there was nothing specific about quantum entanglement, non-locality, or QCD in the book. And although the authors seem to be embracing Feynman's path integrals, they later go back to wave functions to capture the dynamics. Finally, the title of the book suggests that Brin & Jeff favour Hugh Everett's many-world interpretation over the Copenhagen interpretation - I am not sure how that fits with Feynman's approach.
So I ended up being a bit confused. The metaphors frustrated me, and I was not sure I understood where the authors stood 'philosophically' in their interpretation of the quantum world.
In the end, though, I would still recommend this to those who are not yet frustrated by qualitative explanations of this complicated and anti-intuitive subject.
Also, I am not sure the clock-idea is entirely original. The authors clearly start off following an approach to quantum physics inspired by Feynman path integrals (at least that is what I thought lay buried beneath the metaphor of carrying clocks through the universe) and Feynman himself uses stopwatches to aid understanding in his own account on QED. But they do not seem to be touching on a lot of modern stuff - I am not knowledgeable enough to know for sure, but it seemed to me that Brian and Jeff put forward a reasonably dated view of the subject. I believe QED was basically formulated in the 40s, and (unless I missed it) there was nothing specific about quantum entanglement, non-locality, or QCD in the book. And although the authors seem to be embracing Feynman's path integrals, they later go back to wave functions to capture the dynamics. Finally, the title of the book suggests that Brin & Jeff favour Hugh Everett's many-world interpretation over the Copenhagen interpretation - I am not sure how that fits with Feynman's approach.
So I ended up being a bit confused. The metaphors frustrated me, and I was not sure I understood where the authors stood 'philosophically' in their interpretation of the quantum world.
In the end, though, I would still recommend this to those who are not yet frustrated by qualitative explanations of this complicated and anti-intuitive subject.
September 10, 2013
Overview
"The Quantum Universe" is an approachable book that attempts to explain the mathematical ideas underpinning modern quantum theory. In this regard, it is quite different than most other books of its kind. Take Brian Greene's brilliant "The Fabric of the Cosmos," for instance: whereas Greene attempts to provide intuitive descriptions of quantum phenomena, Cox and Forshaw attempt to provide intuition for the mathematics of quantum theory. In other words, whereas most pop modern physics books strive to explain how the quantum world behaves, "The Quantum Universe" is more concerned with explaining the mathematical formalisms we use to describe quantum behavior.
Complex ideas are explained by analogy
If this sounds a bit intimidating, don't worry: there's very little math to be had. As in every good science book for the masses, the authors explain by way of analogy. You're invited to think of "quantum interference" as water waves canceling each other out; of "propagating probability waves" as a set of clocks moving through space; and of logic gates in semiconducters as simple hydraulic valves. For the most part, the analogies are enlightening, and they make a lot of intuitive sense.
That said, this book IS a lot more technical than most of its compatriots. If you've never picked up (and read through!) a popular presentation of modern physics, this probably isn't the place to start. The quantum world is a strange place, and you'll want to make sure you've had some exposure before you let Cox and Forshaw guide you through the particulars. On the other hand, if you've ever felt like every pop physics book tends to rehash the same analogies - and you're ready to probe a bit deeper - "The Quantum Universe" is a breath of fresh air.
Short summary of content
About half of the book is spent explaining electron propagation. The authors do a great job of explaining deeply mathematical ideas without invoking any complex equations. Schrodinger’s wave equation is describe in terms of clocks: "numbers in the complex plane" are replaced by the "clocks," complex addition amounts to "combining clocks," and so. We're told to imagine a propagating probability wave (read: traveling electron) as the aggregate sum of a bunch of winding, traveling clocks, and to find the probability a certain electron will show up at a certain place, you learn to add up all of its clocks and take the height of the resulting hour hand. It all sounds pretty confusing and nonsensical, summarized in a paragraph like this, but the authors really do use this analogy to great effect.
The rest of the book uses this simplified model of electron propagation to explain some pretty deep concepts. The highlight of the book comes when the authors effectively derive the Heisenberg uncertainty principle using nothing but said "clocks" and a clever bit of reasoning. The authors go on to explain why electrons only swirl about atomic nuclei in quantized (read: "discrete") energy levels; they introduce you to the Pauli exclusion principle, and use it to explain why we don't simply fall through the floor; and they attempt to convey the utility of quantum theory by explaining how it led to the development of semiconductors.
Conclusion
The authors probe ambitious depths, and for the most part, they succeed. Unfortunately, they sometimes over-reach. Certain topics, it seems to me, simply cannot be penetrated without fully delving into some serious mathematics. Clocks can only do so much, and as a result, you often have no choice but simply take the authors’ word as they ask you to make one unmotivated leap of faith after another.
Despite this occasional wand-waving, "The Quantum Universe" is a great book. Most books like it focus on describing the quantum weirdness we observe, they as such, they tend to leave you a bit bewildered. Here, Cox and Forshaw focus on explaining how it we're able to model this weirdness, and as a result, you'll leave feeling like it at least makes sense that someone out there really understands this stuff. "The Quantum Universe" appeals to your intuition without dumbing down its subject matter, and if you're willing to delve a bit deeper than usual - and you're still able to surface at the end - you'll come out with a profoundly deeper understanding of the weird, weird ways in which our world works.
Quotes:
"Quantum theory is perhaps the prime example of the infinitely esoteric becoming the profoundly useful" (2)
"The job of quantum theory should be to predict directly observable things... it should not be expected to provide some kind of satisfying mental picture for the internal workings of the atom, because this is not necessary and it may not even be possible." (13)
"We have learned that our perception that objects move smoothly from point to point is, form the perspective of quantum theory, and illusion. It is closer to the truth to suppose that particles move from A to B via all possible paths." (90)
"...point-like particles are really of no size and to as 'What happens if I split an electron in half?' makes no sense at all - there is not meaning to the idea of 'half an electron'." (116)
Appendix: what is a "propagating probability wave"?
To begin with, let's briefly talk about "wave-particle duality." The idea here is that electrons sometimes behave like particles, and other times behave like waves - in other words, electrons are both particles and waves. Huh?
The idea that electrons are particles is fairly intuitive. It’s pretty easy to imagine an electron point orbiting an atomic nucleus. In fact, it turns out that electrons look like particles whenever they're observed: that is, we never detect electron waves. We only detect electron points.
On the other hand, electrons sometimes behave like waves, in that they 'interfere' with one another. If you shoot a bunch of electrons at two tiny side-by-side holes in front of an electron-sensing plate, the electrons hit the plate in a 'striped' pattern. It's as if the electrons were waves - some entering through the right hole, and others through the left - where at some places, the waves cancel out, and at others, they combine. The end result of this ' wave interference' is the observed striped pattern.
But it gets even weirder that this: apparently even a single electron interferes with ITSELF. Let’s say you shoot an electron through the two holes. Once it hits the plate on the other side, you shoot another. You repeat this for a while. At the end of this one-electron-at-a-time experiment, you'll see the same stripped pattern as before. Again, here electrons were all fired in series, and yet, at the end we observe a pattern that indicates interference.
To explain this so-called double-slit experiment, we assume that a single electron is actually many places - at the same time. Essentially, we assume that an electron is a PROBABILITY wave. An electron travels as a sort of "wave of possible electron locations." The wave is "highest" at locations the electron is most likely to be found. And as soon as the wave is observed, or interacts with something, the electron simply manifests itself at a SINGLE location, where the location was picked, at random, from the probability distribution.
This basically means that it makes no sense to ask "what path did the electron take to arrive at the location of measurement"? In a sense, it took EVERY path touched by its probability wave, and in doing so, it "interfered with itself. "
Weird? Totally. True? Almost certainly. Interesting? That’s for you to judge, but cool shit, as far as I’m concerned.
"The Quantum Universe" is an approachable book that attempts to explain the mathematical ideas underpinning modern quantum theory. In this regard, it is quite different than most other books of its kind. Take Brian Greene's brilliant "The Fabric of the Cosmos," for instance: whereas Greene attempts to provide intuitive descriptions of quantum phenomena, Cox and Forshaw attempt to provide intuition for the mathematics of quantum theory. In other words, whereas most pop modern physics books strive to explain how the quantum world behaves, "The Quantum Universe" is more concerned with explaining the mathematical formalisms we use to describe quantum behavior.
Complex ideas are explained by analogy
If this sounds a bit intimidating, don't worry: there's very little math to be had. As in every good science book for the masses, the authors explain by way of analogy. You're invited to think of "quantum interference" as water waves canceling each other out; of "propagating probability waves" as a set of clocks moving through space; and of logic gates in semiconducters as simple hydraulic valves. For the most part, the analogies are enlightening, and they make a lot of intuitive sense.
That said, this book IS a lot more technical than most of its compatriots. If you've never picked up (and read through!) a popular presentation of modern physics, this probably isn't the place to start. The quantum world is a strange place, and you'll want to make sure you've had some exposure before you let Cox and Forshaw guide you through the particulars. On the other hand, if you've ever felt like every pop physics book tends to rehash the same analogies - and you're ready to probe a bit deeper - "The Quantum Universe" is a breath of fresh air.
Short summary of content
About half of the book is spent explaining electron propagation. The authors do a great job of explaining deeply mathematical ideas without invoking any complex equations. Schrodinger’s wave equation is describe in terms of clocks: "numbers in the complex plane" are replaced by the "clocks," complex addition amounts to "combining clocks," and so. We're told to imagine a propagating probability wave (read: traveling electron) as the aggregate sum of a bunch of winding, traveling clocks, and to find the probability a certain electron will show up at a certain place, you learn to add up all of its clocks and take the height of the resulting hour hand. It all sounds pretty confusing and nonsensical, summarized in a paragraph like this, but the authors really do use this analogy to great effect.
The rest of the book uses this simplified model of electron propagation to explain some pretty deep concepts. The highlight of the book comes when the authors effectively derive the Heisenberg uncertainty principle using nothing but said "clocks" and a clever bit of reasoning. The authors go on to explain why electrons only swirl about atomic nuclei in quantized (read: "discrete") energy levels; they introduce you to the Pauli exclusion principle, and use it to explain why we don't simply fall through the floor; and they attempt to convey the utility of quantum theory by explaining how it led to the development of semiconductors.
Conclusion
The authors probe ambitious depths, and for the most part, they succeed. Unfortunately, they sometimes over-reach. Certain topics, it seems to me, simply cannot be penetrated without fully delving into some serious mathematics. Clocks can only do so much, and as a result, you often have no choice but simply take the authors’ word as they ask you to make one unmotivated leap of faith after another.
Despite this occasional wand-waving, "The Quantum Universe" is a great book. Most books like it focus on describing the quantum weirdness we observe, they as such, they tend to leave you a bit bewildered. Here, Cox and Forshaw focus on explaining how it we're able to model this weirdness, and as a result, you'll leave feeling like it at least makes sense that someone out there really understands this stuff. "The Quantum Universe" appeals to your intuition without dumbing down its subject matter, and if you're willing to delve a bit deeper than usual - and you're still able to surface at the end - you'll come out with a profoundly deeper understanding of the weird, weird ways in which our world works.
Quotes:
"Quantum theory is perhaps the prime example of the infinitely esoteric becoming the profoundly useful" (2)
"The job of quantum theory should be to predict directly observable things... it should not be expected to provide some kind of satisfying mental picture for the internal workings of the atom, because this is not necessary and it may not even be possible." (13)
"We have learned that our perception that objects move smoothly from point to point is, form the perspective of quantum theory, and illusion. It is closer to the truth to suppose that particles move from A to B via all possible paths." (90)
"...point-like particles are really of no size and to as 'What happens if I split an electron in half?' makes no sense at all - there is not meaning to the idea of 'half an electron'." (116)
Appendix: what is a "propagating probability wave"?
To begin with, let's briefly talk about "wave-particle duality." The idea here is that electrons sometimes behave like particles, and other times behave like waves - in other words, electrons are both particles and waves. Huh?
The idea that electrons are particles is fairly intuitive. It’s pretty easy to imagine an electron point orbiting an atomic nucleus. In fact, it turns out that electrons look like particles whenever they're observed: that is, we never detect electron waves. We only detect electron points.
On the other hand, electrons sometimes behave like waves, in that they 'interfere' with one another. If you shoot a bunch of electrons at two tiny side-by-side holes in front of an electron-sensing plate, the electrons hit the plate in a 'striped' pattern. It's as if the electrons were waves - some entering through the right hole, and others through the left - where at some places, the waves cancel out, and at others, they combine. The end result of this ' wave interference' is the observed striped pattern.
But it gets even weirder that this: apparently even a single electron interferes with ITSELF. Let’s say you shoot an electron through the two holes. Once it hits the plate on the other side, you shoot another. You repeat this for a while. At the end of this one-electron-at-a-time experiment, you'll see the same stripped pattern as before. Again, here electrons were all fired in series, and yet, at the end we observe a pattern that indicates interference.
To explain this so-called double-slit experiment, we assume that a single electron is actually many places - at the same time. Essentially, we assume that an electron is a PROBABILITY wave. An electron travels as a sort of "wave of possible electron locations." The wave is "highest" at locations the electron is most likely to be found. And as soon as the wave is observed, or interacts with something, the electron simply manifests itself at a SINGLE location, where the location was picked, at random, from the probability distribution.
This basically means that it makes no sense to ask "what path did the electron take to arrive at the location of measurement"? In a sense, it took EVERY path touched by its probability wave, and in doing so, it "interfered with itself. "
Weird? Totally. True? Almost certainly. Interesting? That’s for you to judge, but cool shit, as far as I’m concerned.
January 5, 2022
I know Brian Cox is popular, and he is a good and interesting speaker, but, just me, now, I think it's like listening to a lecturer who knows all the answers and none of the questions.
September 6, 2013
This was an incredibly fascinating yet baffling book. I am quite ashamed to admit that I was confused by Chapter 3! The concept of tiny clocks as a method of understanding quantum waves was so abstract and unusual that I frequently had to remind myself what the clocks were actually representing. Nevertheless, I was perpetually amazed and astonished by the insights into the quantum world that this book elucidated, and I thoroughly enjoyed being forced out of my comfort zone, and having my perspectives challenged continuously.
By the end of the book, I was mentally exhausted (and physically exhausted from concentrating so hard!) yet I learnt a lot of new concepts and I have become more open to new ideas and abstract ways of thinking.
The authors were brilliant. One of the best things about this book was how the authors fused humour and science so that the novel was not like reading a dull, monotonous textbook, but more like talking to a knowledgeable, comprehensible friend. This increased my understanding of certain concepts and held my attention avidly.
Lastly, I absolutely loved the epilogue; it brought together all the ideas learnt throughout the book to demonstrate how these quantum theories can contribute to the understanding of the universe. That, to me, is why science is so wonderful and beautiful.
By the end of the book, I was mentally exhausted (and physically exhausted from concentrating so hard!) yet I learnt a lot of new concepts and I have become more open to new ideas and abstract ways of thinking.
The authors were brilliant. One of the best things about this book was how the authors fused humour and science so that the novel was not like reading a dull, monotonous textbook, but more like talking to a knowledgeable, comprehensible friend. This increased my understanding of certain concepts and held my attention avidly.
Lastly, I absolutely loved the epilogue; it brought together all the ideas learnt throughout the book to demonstrate how these quantum theories can contribute to the understanding of the universe. That, to me, is why science is so wonderful and beautiful.
June 1, 2012
By far NOT my favourite book on quantum physics. I found the authors difficult to follow much of the time, partially because I don't have the maths ability needed for this book. That said, I also found the writers rather boring, sadly. Usually I find this topic very exciting to read.... not this book. I found this book quite tedious and had to force myself to continue reading through the end.
July 10, 2020
Creo que tengo una superposición de estado de fortuna al decidir emprender en el mundo de las reseñas justo con este libro (Afortunado/Desafortunado). La historia es breve. Dije: "Con mi próximo libro terminado haré mi primera reseña". Sin pensar mucho que estaba leyendo divulgación científica sobre la física cuántica. Afortunadamente y gracias a los autores el viaje de la reseña no fue muy complejo.
Lo primero que quiero dejar claro es que a este libro le hice dos viajes para leerlo. El primero por caminos un poco quebrados, cuesta arriba y de lento avance. El puerto fue la mitad del libro. El segundo viaje fue por una autopista de esas que los gringos construyen muy bien. Velocidad de crucero, disfrutar el paisaje y recorrer kilómetros y kilómetros a un extraordinario ritmo. El puerto fue el final del libro y esta reseña.
Se preguntarán la diferencia entre el primer intento y el segundo. Siendo yo el mismo observador ¿Qué pudo haber pasado para que el segundo viaje fuera mucho más exitoso que el primero? La respuesta es un curso de física de la materia que tomé y que me hizo reencontrarme con el libro. Después de conocer de mano de la academia la evolución de la física de la materia desde los filósofos de la antigüedad hasta los experimentos y hallazgos realizados por los aceleradores de partículas contemporáneos mi observador definitivamente cambió.
Conclusión #1 de mi reseña: Si no tiene al menos una noción reciente de física, es posible que su camino se parezca al del intento de mi primer viaje.
Dejando de hablar de mi y pasando al libro es fascinante entender las representaciones de todos los fenómenos del universo a partir de relojes. ¡Leyó bien! Relojes. Los autores parten de una analogía maravillosa en donde introducen al lector a interpretar las partículas fundamentales como si fueran relojes de determinados tamaños y a determinadas horas. La analogía es súper didáctica porque cualquier ser humano es capaz de saber leer la hora de un reloj, por lo tanto con esa información y un poco de razonamiento lógico (o más bien ilógico) usted podrá comprender las historias más fascinantes que explican el funcionamiento del universo.
El abordaje del experimento de doble rendija desde los relojes para explicar el comportamiento ondulatorio de los electrones no es otra cosa más que un desafío a la capacidad de abstracción. Pero una vez superado este fenómeno le quiero decir que se puede graduar cómo conocedor de mecánica cuántica y estar en un selecto 5% (a lo sumo) de personas que en el planeta entienden dicha interpretación.
Al principio me costaba un poco entender esto de los niveles de energía que ocupaban los electrones en los átomos y los experimentos de líneas espectrales no me quedaban para nada claros. El libro es rico en la explicación de este experimento y se entiende de manera clara y simple (Recuerde la conclusión #1 de la reseña) cómo es que se relacionan las líneas espectrales de los elementos químicos con los niveles de energía. Es algo para aplaudir a los científicos que desafían las fronteras del conocimiento, a veces incluso, sin razones aplicables a la práctica.
Para estudiantes flojos de química (como yo) entender los enlaces y reacciones de los elementos en aquellas aburridas clases del pregrado de ingeniería era muy complejo. Aquí los autores se valen de la mecánica cuántica para explicar un sorprendente concepto: Los enlaces y reacciones de los elementos son la manera de actuar de la naturaleza para mantener todo lo que vemos en los mínimos niveles de energía. ¡Wow! Todo lo complejo de esos semestres de química, reducidos a una fórmula de economía.
Otros temas deleitantes como el principio de indeterminación/Incertidumbre de Heisenberg, el de exclusión de Pauli, el descubrimiento del Spin, la interacción entre partículas, la demostración de la masa máxima de las enanas blancas y hasta la concepción del concepto "masa" todos ellos narrados de forma entretenida y simple valieron la pena haberme literalmente DEVORADO este ejemplar.
Recuerde pues que a este libro le metí dos viajes con una sutil diferencia entre el primero y el segundo, pero ese sutil cambio generó una proporcionalidad exponencial en el disfrute. No es necesario pues que tome cursos de física cuántica, tampoco que sea experto en la materia. Solo es desempolvar los conceptos, guardar los relojes digitales y sacar los de manecillas y emprenderse en este viaje... Seguro le va a gustar el libro, porque como dicen los autores "Todo lo que puede suceder, sucede".
Lo primero que quiero dejar claro es que a este libro le hice dos viajes para leerlo. El primero por caminos un poco quebrados, cuesta arriba y de lento avance. El puerto fue la mitad del libro. El segundo viaje fue por una autopista de esas que los gringos construyen muy bien. Velocidad de crucero, disfrutar el paisaje y recorrer kilómetros y kilómetros a un extraordinario ritmo. El puerto fue el final del libro y esta reseña.
Se preguntarán la diferencia entre el primer intento y el segundo. Siendo yo el mismo observador ¿Qué pudo haber pasado para que el segundo viaje fuera mucho más exitoso que el primero? La respuesta es un curso de física de la materia que tomé y que me hizo reencontrarme con el libro. Después de conocer de mano de la academia la evolución de la física de la materia desde los filósofos de la antigüedad hasta los experimentos y hallazgos realizados por los aceleradores de partículas contemporáneos mi observador definitivamente cambió.
Conclusión #1 de mi reseña: Si no tiene al menos una noción reciente de física, es posible que su camino se parezca al del intento de mi primer viaje.
Dejando de hablar de mi y pasando al libro es fascinante entender las representaciones de todos los fenómenos del universo a partir de relojes. ¡Leyó bien! Relojes. Los autores parten de una analogía maravillosa en donde introducen al lector a interpretar las partículas fundamentales como si fueran relojes de determinados tamaños y a determinadas horas. La analogía es súper didáctica porque cualquier ser humano es capaz de saber leer la hora de un reloj, por lo tanto con esa información y un poco de razonamiento lógico (o más bien ilógico) usted podrá comprender las historias más fascinantes que explican el funcionamiento del universo.
El abordaje del experimento de doble rendija desde los relojes para explicar el comportamiento ondulatorio de los electrones no es otra cosa más que un desafío a la capacidad de abstracción. Pero una vez superado este fenómeno le quiero decir que se puede graduar cómo conocedor de mecánica cuántica y estar en un selecto 5% (a lo sumo) de personas que en el planeta entienden dicha interpretación.
Al principio me costaba un poco entender esto de los niveles de energía que ocupaban los electrones en los átomos y los experimentos de líneas espectrales no me quedaban para nada claros. El libro es rico en la explicación de este experimento y se entiende de manera clara y simple (Recuerde la conclusión #1 de la reseña) cómo es que se relacionan las líneas espectrales de los elementos químicos con los niveles de energía. Es algo para aplaudir a los científicos que desafían las fronteras del conocimiento, a veces incluso, sin razones aplicables a la práctica.
Para estudiantes flojos de química (como yo) entender los enlaces y reacciones de los elementos en aquellas aburridas clases del pregrado de ingeniería era muy complejo. Aquí los autores se valen de la mecánica cuántica para explicar un sorprendente concepto: Los enlaces y reacciones de los elementos son la manera de actuar de la naturaleza para mantener todo lo que vemos en los mínimos niveles de energía. ¡Wow! Todo lo complejo de esos semestres de química, reducidos a una fórmula de economía.
Otros temas deleitantes como el principio de indeterminación/Incertidumbre de Heisenberg, el de exclusión de Pauli, el descubrimiento del Spin, la interacción entre partículas, la demostración de la masa máxima de las enanas blancas y hasta la concepción del concepto "masa" todos ellos narrados de forma entretenida y simple valieron la pena haberme literalmente DEVORADO este ejemplar.
Recuerde pues que a este libro le metí dos viajes con una sutil diferencia entre el primero y el segundo, pero ese sutil cambio generó una proporcionalidad exponencial en el disfrute. No es necesario pues que tome cursos de física cuántica, tampoco que sea experto en la materia. Solo es desempolvar los conceptos, guardar los relojes digitales y sacar los de manecillas y emprenderse en este viaje... Seguro le va a gustar el libro, porque como dicen los autores "Todo lo que puede suceder, sucede".
May 29, 2021
W większości książka ciekawa i napisana w dość prosty sposób. Końcówka mocno wymagająca
May 26, 2020
Todas las posibles maneras para divulgar la teoría cuántica han sido probadas. TODAS.
Creo que ninguna, hasta ahora, ha conseguido su objetivo final: hacer creer a un número significativo de personas que no son profesionales de la física que la teoría cuántica puede entenderse (aclaro que los que somos profesionales tampoco la entendemos, solo la usamos).
Este libro no es la excepción dentro de la innumerable cantidad de textos que buscan ese "santo grial" de la divulgación de la teoría cuántica. No, después de leer "El universo cuántico" tampoco entenderás la teoría cuántica.
Pero ¿es esa una razón para no leer el libro? ¡de ninguna manera!
Y es que la teoría cuántica no puede "entenderse" en el sentido tradicional de la palabra. Cuando decimos que "entendí una teoría o una visión del mundo" lo que queremos decir es que creamos un modelo de lo que nos explicaron usando objetos y fenómenos con los que hemos tenido contacto antes. Para entender el calor y su relación con las moléculas no hace falta ver una molécula, basta pensar en las balotas en una tómbola o en una piscina de pelotas.
Tampoco puede darse sentido a lo cuántico usando la lógica del mundo clásico: causa->efecto->causa->efecto.
No son por tanto los libros los que fracasan, son las expectativas del lector.
¿Cómo entonces "acercarse" a lo cuántico sin entenderlo? Mi recomendación como profesional de la física es hacerlo, justamente, leyendo la mayor diversidad posible de aproximaciones a los "objetos", los fenómenos, la lógico de lo cuántico.
Allí es precisamente donde este libro tiene un valor, para mí, con pocos precedentes en la literatura divulgativa de lo cuántico.
Muchos libros sobre el tema son una repetición incansable de los mismos temas (lo que es realmente muy bueno para acercarse a lo cuántico: repetir, repetir, repetir). Pero este hace una aproximación novedosa.
En lugar de usar la clásica explicación de los fenómenos cuánticos basada en la función de onda, que es descrita por muchos textos casi como una onda real, el texto usa una aproximación basada en el formalismo del propagador que podría describirse como la idea de que una entidad cuántica (un electrón por ejemplo) se divide (imaginariamente) en una infinidad de partículas que recorren el mundo por todos los caminos posibles. En cada lugar del espacio y el tiempo estas versiones imaginarias del objeto original tienen una propiedad cuántica que se asemeja a un "reloj" que marca una hora (fase) y tiene un tamaño (magnitud). La interacción de estas partículas imaginarias con observadores y otras partículas son las que determinan finalmente el desenlace de los fenómenos asociados al sistema original.
Esta idea termina extendiéndose muy bien cuando se trata de explicar la teoría cuántica de campos, uno de los más temas más difíciles de divulgar. La manera como este libro trata el tema (especialmente en lo que respecta a la electrodinámica cuántica) es muy novedosa y a mi, que supuestamente soy físico, terminó aclarándome algunos conceptos que no entendía muy bien.
Solo hay un problema serio con el libro: es incomprensible para un lector que se acerca por primera vez a la teoría cuántica.
Este es un libro para leer después de saber algo de teoría cuántica o de haber leído muchas aproximaciones diferentes a la teoría o repetido varias veces las mismas aproximaciones a las que nos tienen acostumbrados la mayoría de los textos divulgativos en el tema.
Este es también un buen libro para aquellos profesionales que queremos divulgar mejor la teoría cuántica y la física de la materia en general. La forma como describe y explica la conducción o no conducción de electrones en los sólidos es muy interesante y no muy común en textos divulgativos a este nivel. ¡Vale la pena leerlo!
En síntesis: 1) los que no saben mucho de teoría cuántica deberían alejarse de este libro (pero regresar a él después de leer otros más sencillos), 2) los que ya saben de teoría cuántica y no son profesionales, disfruten esta nueva aproximación (pero háganse a la idea que todavía no entenderán la teoría), 3) los que son profesionales y quieren o necesitan divulgar la teoría cuántica lean especialmente los capítulos dedicados a las moléculas, los sólidos y las interacciones fundamentales ¡son muy originales!
Si al fin descubriste que no puedes entender la teoría cuántica, al menos acostúmbrate a ello.
Creo que ninguna, hasta ahora, ha conseguido su objetivo final: hacer creer a un número significativo de personas que no son profesionales de la física que la teoría cuántica puede entenderse (aclaro que los que somos profesionales tampoco la entendemos, solo la usamos).
Este libro no es la excepción dentro de la innumerable cantidad de textos que buscan ese "santo grial" de la divulgación de la teoría cuántica. No, después de leer "El universo cuántico" tampoco entenderás la teoría cuántica.
Pero ¿es esa una razón para no leer el libro? ¡de ninguna manera!
Y es que la teoría cuántica no puede "entenderse" en el sentido tradicional de la palabra. Cuando decimos que "entendí una teoría o una visión del mundo" lo que queremos decir es que creamos un modelo de lo que nos explicaron usando objetos y fenómenos con los que hemos tenido contacto antes. Para entender el calor y su relación con las moléculas no hace falta ver una molécula, basta pensar en las balotas en una tómbola o en una piscina de pelotas.
Tampoco puede darse sentido a lo cuántico usando la lógica del mundo clásico: causa->efecto->causa->efecto.
No son por tanto los libros los que fracasan, son las expectativas del lector.
¿Cómo entonces "acercarse" a lo cuántico sin entenderlo? Mi recomendación como profesional de la física es hacerlo, justamente, leyendo la mayor diversidad posible de aproximaciones a los "objetos", los fenómenos, la lógico de lo cuántico.
Allí es precisamente donde este libro tiene un valor, para mí, con pocos precedentes en la literatura divulgativa de lo cuántico.
Muchos libros sobre el tema son una repetición incansable de los mismos temas (lo que es realmente muy bueno para acercarse a lo cuántico: repetir, repetir, repetir). Pero este hace una aproximación novedosa.
En lugar de usar la clásica explicación de los fenómenos cuánticos basada en la función de onda, que es descrita por muchos textos casi como una onda real, el texto usa una aproximación basada en el formalismo del propagador que podría describirse como la idea de que una entidad cuántica (un electrón por ejemplo) se divide (imaginariamente) en una infinidad de partículas que recorren el mundo por todos los caminos posibles. En cada lugar del espacio y el tiempo estas versiones imaginarias del objeto original tienen una propiedad cuántica que se asemeja a un "reloj" que marca una hora (fase) y tiene un tamaño (magnitud). La interacción de estas partículas imaginarias con observadores y otras partículas son las que determinan finalmente el desenlace de los fenómenos asociados al sistema original.
Esta idea termina extendiéndose muy bien cuando se trata de explicar la teoría cuántica de campos, uno de los más temas más difíciles de divulgar. La manera como este libro trata el tema (especialmente en lo que respecta a la electrodinámica cuántica) es muy novedosa y a mi, que supuestamente soy físico, terminó aclarándome algunos conceptos que no entendía muy bien.
Solo hay un problema serio con el libro: es incomprensible para un lector que se acerca por primera vez a la teoría cuántica.
Este es un libro para leer después de saber algo de teoría cuántica o de haber leído muchas aproximaciones diferentes a la teoría o repetido varias veces las mismas aproximaciones a las que nos tienen acostumbrados la mayoría de los textos divulgativos en el tema.
Este es también un buen libro para aquellos profesionales que queremos divulgar mejor la teoría cuántica y la física de la materia en general. La forma como describe y explica la conducción o no conducción de electrones en los sólidos es muy interesante y no muy común en textos divulgativos a este nivel. ¡Vale la pena leerlo!
En síntesis: 1) los que no saben mucho de teoría cuántica deberían alejarse de este libro (pero regresar a él después de leer otros más sencillos), 2) los que ya saben de teoría cuántica y no son profesionales, disfruten esta nueva aproximación (pero háganse a la idea que todavía no entenderán la teoría), 3) los que son profesionales y quieren o necesitan divulgar la teoría cuántica lean especialmente los capítulos dedicados a las moléculas, los sólidos y las interacciones fundamentales ¡son muy originales!
Si al fin descubriste que no puedes entender la teoría cuántica, al menos acostúmbrate a ello.
March 13, 2020
Удивительная книга!
August 30, 2012
First, a disclaimer. I have a degree in Physics so have studied Quantum Mechanics (QM) at degree level. Therefore I didn't read this as a lay person (it's intended target audience), so YMMV.
I was hoping that if anyone could make QM accessible to the layman it would be Prof. Brain Cox. Sadly, in my opinion, this isn't the case.
The book starts with a brief history of the beginning of the subject (which I found interesting), but when the author starts to describe the actual theory things start to unravel. In what I assume is an attempt to reduce the amount of maths in the book, he uses a 'clock system' to try and explain the theory. To my mind trying to explain it this way made no sense - if you don't have a solid understanding of the basics of the subject then you stand no chance of understanding the harder stuff once you reach it, and to truly understand the basics you need to understand the maths.
Approximately half way through the clock system is retired and maths starts to assert itself. I could almost hear the author think 'hmmm, this clock thing isn't really working, I'm going to have to start using maths'. However by then I think it's too little too late.
It wasn't all bad though; I enjoyed the last chapter on the death of stars. However overall this book reinforced my opinion that it's not possible to understand QM without a suitable high level understanding of maths (despite how elitist that may sound!).
I was hoping that if anyone could make QM accessible to the layman it would be Prof. Brain Cox. Sadly, in my opinion, this isn't the case.
The book starts with a brief history of the beginning of the subject (which I found interesting), but when the author starts to describe the actual theory things start to unravel. In what I assume is an attempt to reduce the amount of maths in the book, he uses a 'clock system' to try and explain the theory. To my mind trying to explain it this way made no sense - if you don't have a solid understanding of the basics of the subject then you stand no chance of understanding the harder stuff once you reach it, and to truly understand the basics you need to understand the maths.
Approximately half way through the clock system is retired and maths starts to assert itself. I could almost hear the author think 'hmmm, this clock thing isn't really working, I'm going to have to start using maths'. However by then I think it's too little too late.
It wasn't all bad though; I enjoyed the last chapter on the death of stars. However overall this book reinforced my opinion that it's not possible to understand QM without a suitable high level understanding of maths (despite how elitist that may sound!).
June 11, 2013
As I had studied quantum mechanics at university in the late 1960s as part of my chemistry degree I had a good idea what to expect from this book but, nevertheless, I found much of it very confusing. In particular, the use of the clocks, and the rules for the winding thereof, didn't help. These were supposedly introduced to avoid the use of complex mathematics but personally I would have done better struggling with the maths than trying to visualise these pesky clocks.
It also seemed to me that few of the chapters summarised what had been said or drew any conclusions to pull together what had been discussed. I think that with a subject like this there needs to be some pauses to pull together the story so far to make sure that the audience is still on board. (Although who that intended audience is, I can't be sure.)
I'm writing this review a couple of months after finishing the book and, to be honest, I can remember little of the book over and above what I already knew before I read it. Overall, I was expecting better than this from Brian Cox, given his renowned reputation as a television science communicator, so I wonder if having two authors isn't the root of the problem. Perhaps either author working alone would have done better than the two acting together. As it is, I've been put off reading anything else written by either of them!
It also seemed to me that few of the chapters summarised what had been said or drew any conclusions to pull together what had been discussed. I think that with a subject like this there needs to be some pauses to pull together the story so far to make sure that the audience is still on board. (Although who that intended audience is, I can't be sure.)
I'm writing this review a couple of months after finishing the book and, to be honest, I can remember little of the book over and above what I already knew before I read it. Overall, I was expecting better than this from Brian Cox, given his renowned reputation as a television science communicator, so I wonder if having two authors isn't the root of the problem. Perhaps either author working alone would have done better than the two acting together. As it is, I've been put off reading anything else written by either of them!
August 27, 2018
The title and cover turn me off since the title implies the many-worlds interpretation and the cat implies the Copenhagen interpretation, but luckily that isn't what this book is about. The authors endorse the many-worlds interpretation, but the issue of interpretation occupies only about 2 pages. This is about something else.
They also don't spend much time on the double-slit experiment, entanglement, wave-particle duality, or any of the other old chestnuts. The main meat of this book, covering the final half of it, is the Pauli exclusion principle. This is the rule that says, basically, no two electrons in a system can be in the same quantum state.
Is there really half a book's worth of stuff to say about that? Absolutely!
The most common application is to electron orbitals in an atom or molecule. This simple principle (plus a few other things) gives rise to the differences between atoms of different elements, and thus to all of chemistry. It also explains the difference between conductors, insulators and semiconductors. And the emission/absorption spectra of atoms and molecules. It even explains why white dwarf stars exist, and what their maximum mass is. (An appendix contains a detailed rough sketch of how to calculate that mass. It is the only part of the book with detailed equations.)
I studied the exclusion principle in school. In grad school we did the calculations for energy levels in hydrogen atoms. We did part of the calculations for energy levels in helium. We did calculations for energy levels in hydrogen molecules, demonstrating that the lower energy state causes them to form and calculating the mean distance between the nuclei those molecules. (I nearly decided to do my Ph.D. research on related computations for larger systems.) I mention this to point out that when studying this stuff in school, we tended to focus on the calculations ("Shut up and calculate!") and not on the deeper meanings. As the two hydrogen nuclei are moved further and further apart, the influence of them on each other gets smaller and smaller until it becomes negligible for all practical purposes, so we didn't worry about it. But.... if you trust the math, and trust that the formulas are a complete description, the mutual influence, due to the exclusion principle, cannot ever actually go to zero. Even if moved to opposite sides of the galaxy, the exclusion principle still states that the electrons in those two atoms cannot have exactly the same energy levels. In fact, no two electrons in any two atoms in the entire universe can be in exactly the same state! In some sense, every electron in the universe is influenced by every other electron in the universe. That is mind-blowing and hard to believe. I pretty much expect that there is something, somewhere that we don't know yet that makes the interaction go to zero after sufficient distance, maybe due to quantization of space or who-knows-what, but based on the existing math in the existing model, that doesn't happen. Compared to an atom, white dwarf stars are huge, yet the principle clearly still applies to them.
As for the subtitle "...anything that can happen, does," that is referring both to the many-worlds interpretation (yuck!) and the principle of least action. It goes something like this. Newton described motion in terms of 3 laws, all of which are stated in terms of local things affecting an object at some point. But it is possible to derive those same laws by inventing (from thin air) some quantity called the action and noting that the path taken by a moving object (under appropriate conditions) can be calculated either by the laws as Newton wrote them, or by considering all possible paths that the object could take, and finding the one where the sum of the "action" along those paths is minimized. It is "as if" the object tried all the possible paths and then picked the one that took least action. In quantum mechanics, a similar action approach can be used to determine the path of a particle. We construct something called the "path integral" which is a pain-in-the-butt to calculate, but basically considers all the possible wave functions generated by considering the photon or electron or whatever taking every possible path to get from A to B, and add all those possibilities together and most of the wave functions cancel each other out except along one path and thus that is the path the photon or electron took. In class we treated this mostly as a computational trick, but some, including these authors treat it as actual fact: the particle really did explore all possible paths. I find that hard to accept. But the universe doesn't care what I accept, and whether real or just a computational trick, the math does generate the right answer.
To avoid equations in the book, the authors describe a wave function as little clocks located at points in space, rather than using the notion of complex numbers. Some reviewers here were really turned-off by this. Initially, I was, too. The authors have to explain how to add, and eventually how to multiply, these little clocks by each other, so I thought they might as well just explain complex numbers: they aren't all that hard. But the more I think about it, the more I like the clock idea. They have to talk about these quite a lot. The word "clock" is one syllable, while "complex number" is four and "value of the wave function" is seven, so saying "clock" saves a lot of time as well as removing the need for equations. Eliminating equations helps with the tree vs. forest problem that could otherwise come up. You can focus on the big picture, and not try to deal so much with the equations. (In other words, the opposite of my college experience.)
I have no idea which people will or will not get something out of this book, but it was very useful and thought-provoking for me, even though I've read and studied about QM for years.
By the way, Brian Cox is apparently known from TV in Britain, but is someone I previously didn't know.
Trigger warning: this book contains frequent use of the word "learnt" which is an accepted variant spelling, but annoying to me.
They also don't spend much time on the double-slit experiment, entanglement, wave-particle duality, or any of the other old chestnuts. The main meat of this book, covering the final half of it, is the Pauli exclusion principle. This is the rule that says, basically, no two electrons in a system can be in the same quantum state.
Is there really half a book's worth of stuff to say about that? Absolutely!
The most common application is to electron orbitals in an atom or molecule. This simple principle (plus a few other things) gives rise to the differences between atoms of different elements, and thus to all of chemistry. It also explains the difference between conductors, insulators and semiconductors. And the emission/absorption spectra of atoms and molecules. It even explains why white dwarf stars exist, and what their maximum mass is. (An appendix contains a detailed rough sketch of how to calculate that mass. It is the only part of the book with detailed equations.)
I studied the exclusion principle in school. In grad school we did the calculations for energy levels in hydrogen atoms. We did part of the calculations for energy levels in helium. We did calculations for energy levels in hydrogen molecules, demonstrating that the lower energy state causes them to form and calculating the mean distance between the nuclei those molecules. (I nearly decided to do my Ph.D. research on related computations for larger systems.) I mention this to point out that when studying this stuff in school, we tended to focus on the calculations ("Shut up and calculate!") and not on the deeper meanings. As the two hydrogen nuclei are moved further and further apart, the influence of them on each other gets smaller and smaller until it becomes negligible for all practical purposes, so we didn't worry about it. But.... if you trust the math, and trust that the formulas are a complete description, the mutual influence, due to the exclusion principle, cannot ever actually go to zero. Even if moved to opposite sides of the galaxy, the exclusion principle still states that the electrons in those two atoms cannot have exactly the same energy levels. In fact, no two electrons in any two atoms in the entire universe can be in exactly the same state! In some sense, every electron in the universe is influenced by every other electron in the universe. That is mind-blowing and hard to believe. I pretty much expect that there is something, somewhere that we don't know yet that makes the interaction go to zero after sufficient distance, maybe due to quantization of space or who-knows-what, but based on the existing math in the existing model, that doesn't happen. Compared to an atom, white dwarf stars are huge, yet the principle clearly still applies to them.
As for the subtitle "...anything that can happen, does," that is referring both to the many-worlds interpretation (yuck!) and the principle of least action. It goes something like this. Newton described motion in terms of 3 laws, all of which are stated in terms of local things affecting an object at some point. But it is possible to derive those same laws by inventing (from thin air) some quantity called the action and noting that the path taken by a moving object (under appropriate conditions) can be calculated either by the laws as Newton wrote them, or by considering all possible paths that the object could take, and finding the one where the sum of the "action" along those paths is minimized. It is "as if" the object tried all the possible paths and then picked the one that took least action. In quantum mechanics, a similar action approach can be used to determine the path of a particle. We construct something called the "path integral" which is a pain-in-the-butt to calculate, but basically considers all the possible wave functions generated by considering the photon or electron or whatever taking every possible path to get from A to B, and add all those possibilities together and most of the wave functions cancel each other out except along one path and thus that is the path the photon or electron took. In class we treated this mostly as a computational trick, but some, including these authors treat it as actual fact: the particle really did explore all possible paths. I find that hard to accept. But the universe doesn't care what I accept, and whether real or just a computational trick, the math does generate the right answer.
To avoid equations in the book, the authors describe a wave function as little clocks located at points in space, rather than using the notion of complex numbers. Some reviewers here were really turned-off by this. Initially, I was, too. The authors have to explain how to add, and eventually how to multiply, these little clocks by each other, so I thought they might as well just explain complex numbers: they aren't all that hard. But the more I think about it, the more I like the clock idea. They have to talk about these quite a lot. The word "clock" is one syllable, while "complex number" is four and "value of the wave function" is seven, so saying "clock" saves a lot of time as well as removing the need for equations. Eliminating equations helps with the tree vs. forest problem that could otherwise come up. You can focus on the big picture, and not try to deal so much with the equations. (In other words, the opposite of my college experience.)
I have no idea which people will or will not get something out of this book, but it was very useful and thought-provoking for me, even though I've read and studied about QM for years.
By the way, Brian Cox is apparently known from TV in Britain, but is someone I previously didn't know.
Trigger warning: this book contains frequent use of the word "learnt" which is an accepted variant spelling, but annoying to me.
September 16, 2012
Probably the most annoying thing about this book is that it claims you don't need the maths to understand it, then proceeds to fill every page with maths. After one long equation filled section it rubs your face in it by saying, basically, that you needn't have bothered.
With quantum physics relying so much on maths to be explained, it seems rather glib to claim you don't need to understand it, but then again how could they have sold this as a pop-science book if you needed a degree in maths to read it? I guess you'd also be left with a very thin book on quantum physics if you didn't pad it out with equations.
This book seems aimless: Too complicated for the typical pop-science fans of Brian Cox, too lightweight for the kind of people who actually need to understand quantum physics.
With quantum physics relying so much on maths to be explained, it seems rather glib to claim you don't need to understand it, but then again how could they have sold this as a pop-science book if you needed a degree in maths to read it? I guess you'd also be left with a very thin book on quantum physics if you didn't pad it out with equations.
This book seems aimless: Too complicated for the typical pop-science fans of Brian Cox, too lightweight for the kind of people who actually need to understand quantum physics.
June 20, 2019
A very interesting and highly educational book. Brian Cox takes what could be classed as a complex topic and translates it into a easy to read, follow and understand topic. This book would appeal to students probably at University level, and people that are interested in the Quantum universe. No editorial issues in the book, structured well, more of a educational book than a book for pleasure. Only negative, is that the book cover is a bit plain in my opinion, other than that, a decent book. Glad I read it, learnt allot of new things from this book.
August 30, 2022
Please stop talking about clocks
September 25, 2020
The Quantum Universe is, of course, entertainingly written and absolutely fascinating but that is about all the critique I am qualified to make. I read this book only in the sense that my eyes passed over each sentence from page one until I got to the end. If the subtitle, ‘Everything That Can Happen Does Happen’, is correct then I am incapable of understanding quantum theory. It’s at least nice to have one’s ignorance raised to the level of a general principle. Readers without mathematical background beware. For you if you’ve ever wondered why we don’t fall through the floor.
July 23, 2012
An excellent and accessible overview of how quantum mechanics actually works. Yes, there's some math in here, but you can't really explain quantum mechanics without probability.
Now I know how to respond to all the Deepak Chopra wanna-bes and fans of "What the Bleep Do We Know" who think there's something mystical in their misunderstanding of quantum mechanics. And I understand what the Higgs Boson is!
Now I know how to respond to all the Deepak Chopra wanna-bes and fans of "What the Bleep Do We Know" who think there's something mystical in their misunderstanding of quantum mechanics. And I understand what the Higgs Boson is!
December 20, 2011
A good in-depth (for the average non-physicist) look at some commonly misunderstand aspects of quantum theory. This book can take you from zero understanding to a relatively comprehensive understanding in under 300 pages. It delivers that which it promises, nothing more, nothing less. Worth a read.
April 20, 2023
"As we'll see in a moment, the clock faces will allow us to do just this because they are able to keep track of the relative positions of the peaks and troughs of the waves"
The Quantum Universe by Brian Cox
No unfortunately we will not... Like most of the other reviews for this, the introduction of the clock analogy made a good portion of this book almost unreadable for me. To be fair, I'm not that attached to analogies in general but this one was simply intuitively wrong for me. Without going into to much detail and in hopes of simplifying the whole matter, Dr. Cox attempts to align quantum energy states and their associated wave or particle functions with that of clocks. I think one of the problems I had with this was he kept using this idea of winding back the clock necessitating a timer functionality which wasn't the premise of his clock idea in terms of wave functions. He uses this analogy over and over again, adding and taking away rules at whim eternally confusing his audience.
There are some good parts to this, he does a brilliant job of depicting the ruthless takeover of semiconductor technologies. Cox compares how many transistors we make every day to the amount of rice eaten by the entire world. Some decent introductions to notable Physicists and a good flow of historical understandings of QED.
I really enjoy listening to Dr. Cox talk about the universe. Actually even more than Feynman I think. However, my first encounter with his writing was subpar and I hope this was simply a probabilistic fumble of sorts for him. (To keep with the quantum probabilities theme :) ). Some of this was sort of dense and not actually for a layman... He introduces a quasi-math that of course confused me even more. Not to bad overall but certainly not great.
The Quantum Universe by Brian Cox
No unfortunately we will not... Like most of the other reviews for this, the introduction of the clock analogy made a good portion of this book almost unreadable for me. To be fair, I'm not that attached to analogies in general but this one was simply intuitively wrong for me. Without going into to much detail and in hopes of simplifying the whole matter, Dr. Cox attempts to align quantum energy states and their associated wave or particle functions with that of clocks. I think one of the problems I had with this was he kept using this idea of winding back the clock necessitating a timer functionality which wasn't the premise of his clock idea in terms of wave functions. He uses this analogy over and over again, adding and taking away rules at whim eternally confusing his audience.
There are some good parts to this, he does a brilliant job of depicting the ruthless takeover of semiconductor technologies. Cox compares how many transistors we make every day to the amount of rice eaten by the entire world. Some decent introductions to notable Physicists and a good flow of historical understandings of QED.
I really enjoy listening to Dr. Cox talk about the universe. Actually even more than Feynman I think. However, my first encounter with his writing was subpar and I hope this was simply a probabilistic fumble of sorts for him. (To keep with the quantum probabilities theme :) ). Some of this was sort of dense and not actually for a layman... He introduces a quasi-math that of course confused me even more. Not to bad overall but certainly not great.
February 18, 2018
El Universo Cuántico de Brian Cox es una obra de divulgación para usuarios que ya tienen cierto nivel base en mecánica cuántica, así como nociones sobre formulación matemática basica.
Muy recomendado para usuarios que llevan tiempo dentro de la temática y estén interesados en repasar conceptos como momento, reloj o pozo de potencial. Hace especial hincapié en las escalas de ordenamiento y incluye perspectivas muy bien expuestas e interesantes acerca del Principio de exclusión de Pauli y el entrelazamiento cuántico.
No es una obra de arte que te atrape como lo hace por ejemplo el Gran Diseño de Stephen Hawking, pero si una herramienta excepcional para comprender mejor los fenómenos cuánticos con ingeniosas representaciones mentales que cada vez que regresen a tu mente te recordarán la esencia de ese simpático gatete que define la portada.
Muy recomendado para usuarios que llevan tiempo dentro de la temática y estén interesados en repasar conceptos como momento, reloj o pozo de potencial. Hace especial hincapié en las escalas de ordenamiento y incluye perspectivas muy bien expuestas e interesantes acerca del Principio de exclusión de Pauli y el entrelazamiento cuántico.
No es una obra de arte que te atrape como lo hace por ejemplo el Gran Diseño de Stephen Hawking, pero si una herramienta excepcional para comprender mejor los fenómenos cuánticos con ingeniosas representaciones mentales que cada vez que regresen a tu mente te recordarán la esencia de ese simpático gatete que define la portada.
January 13, 2025
For a topic that twists reality into a pretzel, I’ll admit—it’s well-explained given the mind-bending complexity. The authors do their best to guide you through quantum wonderland without letting your brain melt entirely.
But also a reminder that when it comes to quantum physics, we’re all Schrödinger’s students—simultaneously understanding and completely lost.
On a lighter note: why did the quantum physicist break up with reality? Because he just needed more space.
But here’s the real kicker: just as you’re dangling over the precipice of incomprehension, they drop this gem after explaining something baffling: “Which may sound alarming, but the math can handle it.” Honestly, that’s the most comforting thing they’ve said in the whole book. Forget philosophical reassurances—apparently, cold hard equations have your back.
But also a reminder that when it comes to quantum physics, we’re all Schrödinger’s students—simultaneously understanding and completely lost.
On a lighter note: why did the quantum physicist break up with reality? Because he just needed more space.
But here’s the real kicker: just as you’re dangling over the precipice of incomprehension, they drop this gem after explaining something baffling: “Which may sound alarming, but the math can handle it.” Honestly, that’s the most comforting thing they’ve said in the whole book. Forget philosophical reassurances—apparently, cold hard equations have your back.
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