Is Einstein Still Right?: Black Holes, Gravitational Waves, and the Quest to Verify Einstein's Greatest Creation

by Clifford M. Will, Nicolas Yunes

Albert Einstein is often viewed as the icon of genius, and his theories are admired for their beauty and correctness. Yet the final judge of any theory is the rigorous test of experiment, not the fame of its inventor or the allure of its mathematics. For decades, general relativity has passed test after test with flying colors, including some remarkable new tests using the recently detected gravitational waves.

Still, there are reasons for doubt. Einstein's theory of gravity, as beautiful as it is, seems to be in direct contradiction with another theory he helped quantum mechanics. Until recently, this was considered to be a purely academic affair. But as more and more data pour in from the most distant corners of the universe, hinting at bizarre stuff called "dark energy" and "dark matter," some scientists have begun to explore the possibility that Einstein's theory may not provide a complete picture of the cosmos.

This book chronicles the latest adventures of scientists as they put Einstein's theory to the test in ever more precise and astonishing ways, and in ever more extreme situations, when gravity is unfathomably intense and rapidly churning. From the explosions of neutron stars and the collisions of black holes to the modern scientific process as a means to seek truth and understanding in the cosmos, this book takes the reader on a journey of learning and discovery that has been 100 years in the making.

Genres: Physics, Science

306 pages, Hardcover

Published October 1, 2020

Reviews

[Brian Clegg · Rating 3 out of 5]

If there's one thing that gets a touch tedious in science reporting it's the news headlines that some new observation or experiment 'proves Einstein right' - as if we're still not sure about relativity. At first glance that's what this book does too, but in reality Clifford Will and Nicolas Yunes are celebrating the effectiveness of the general theory of relativity, while being conscious that there may still be situations where, for whatever reason, the general theory is not sufficient.

It's a genuinely interesting book - what Will and Yunes do is take experiments that are probably familiar to the regular popular science reader already and expand on the simplified view of them we are usually given. So, for example, one of the first things they mention is the tower experiments to show the effect of gravitational red shift. I was aware of these experiments, but what we get here goes beyond the basics of the conceptual experiment to deal with the realities of dealing with physical objects where, for example, heat can cause movement of atoms, corrupting a very small observational shift.

After this first example, Will and Yunes go on to cover deflection of light observed during eclipses, including both the original 1919 Eddington observation (they support the results which have been queried by some historians of science) and a recent recreation using modern amateur equipment which did far better. We get the opposing time effects of the general and special theories, including the usual GPS example, gravitational waves (of course), experiments to determine the effect of frame dragging and considerably more.

All this was interesting, but what the book really lacks is any sense of narrative. We are told lots of information, but there's a slight feeling for the reader of 'And...?' Although the authors present much of this information well, they can suffer from a common communication problem when physicists try to explain physics to a general audience - they can't really understand what the rest of us struggle to get our heads around. So, for example, relatively simple explanations, such as the path of light being warped as it crosses an accelerating spaceship, and from the equivalence principle, the expectation of the same thing happening under the influence of gravity, are quite difficult to follow here.

For the right audience, which I think might be someone about to start a physics degree, this is an excellent book, but I'm not sure it quite works for a general reader.

[Kam Yung Soh · Rating 5 out of 5]

A great book about the various tests that Einstein's General Relativity (GR) have been put through since it was proposed. Spoiler alert, GR has passed all the tests so far, while alternative theories of gravity have not. A follow up to one of the author's earlier book, "Was Einstein Right?", this book covers much of the same ground, but updates it with some of the latest experiments that have been performed to verify the predictions of GR.

Many aspects of GR, from the effects of gravity on space-time, to how black holes twist and turn space-time and light, are covered in the book, along with historical and current experiments done to prove (or disprove) GR. Some of the tests involving astrophysics (like stars orbiting black holes, imaging black holes and gravitational waves) are the latest, and most dramatic, examples of GR in action and are still ongoing. The hope is that in such the extreme environments, deviations from the predictions of GR will appear, pointing the way to new physics and perhaps unifying quantum theory with GR.

But don't hold your breath; odds are GR will still work, and the hunt to find yet more precise tests of GR will have to continue for some time to come.

[Bicyclejim · Rating 5 out of 5]

Excellent book, though some parts I will read again. The authors convey the many, many tests of general relativity in language that anyone can understand. I particularly enjoyed the later chapters on gravitational waves, black holes, and the future of gravitational wave "listening".

[TomAmazon · Rating 3 out of 5]

Good stories though.

While the book goes through all sorts of great stories about gravity, it leaves me a little underwhelmed. It’s not the subject.

Maybe it’s me, I’m just too familiar with the physics. The whole thing starts off negative with the usual unsubstantiated claims about the superiority of QM, then relaxes into some nice tales.

[Mark · Rating 4 out of 5]

Very interesting. One has to have an interest in the subject, but the book is quite readable for the most part. One or two spots take a bit of study or are helped if one has had freshman physics. Over all a very good book.

[Nisham Mohammed · Rating 3 out of 5]

Has interesting parts. But not organized in compelling manor