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“de Finetti in 1974 wrote: "My thesis… is...probability does not exist… only subjective probabilities exist, the degree of belief in the occurrence of an event attributed by a given person at a given instant and with a given set of information."…Throughout our lives, most of us gain confidence in subjective probabilities because we find that results we deem likely happen often, and those that we don't happen rarely.”

“Everett's framework, in which probabilities wiggle their way into quantum theory in a more subtle…way, much like the way probability enters our thinking in day-to-day life. Whether we ponder the weather, the lottery, or the shape of the next gravitational wave passing through planet Earth, we all use subjective probabilities all the time to quantify our uncertainty in situations where we have incomplete knowledge.”

“Everett himself said he sought somehow to bridge the positions of Einstein and Bohr. He claimed their differences were a matter of perspective and described his scheme as "objectively deterministic, with probability appearing at the subjective level." This is an interesting point. In the early Copenhagen formulation of quantum mechanics, probabilities were axiomatic and fundamental.”

“Everett pulled down Bohr's wall separating the quantum microworld from the classical macroworld. His key idea was to take the math behind quantum mechanics seriously and to apply it to everything. Suppose there is no collapse, he suggested, but only a single universal wave function that includes observers and everything else, evolving gently and smoothly...”

“Niels Bohr, on the other hand, who had a background in philosophy as well as mathematics, had a profound intuition that quantum mechanics was consistent. Bohr took seriously the central tenet of quantum mechanics that observership—the very questions we ask of nature—affects how nature manifests itself. "No phenomenon is a real phenomenon until it is an observed phenomenon," he held.”

“To Einstein, the probabilistic nature of quantum mechanics signaled that the theory was incomplete, that there had to be a deeper-lying framework that permitted an objectively real description of physical reality, regardless of any acts of observation. "The [quantum] theory produces a good deal but hardly brings us closer to the secret of the Old One," he wrote to Bohr. "I am convinced...He does not play dice"”

“[Stephen:] The history of the universe depends on the question you ask. Good night.”

“Stephen put together one more line: "I think that a proper quantum outlook (onto the universe] will lead to a different philosophy of cosmology in which we work from the top down, backward in time, starting from the surface of our observations." I was startled—Stephen's new top-down philosophy would seem to upend the relation between cause and effect in cosmological theory.”

“The Cartesian answer to the scientific revolution was to move the Archimedean point inward, to man himself, and to choose the human mind as the ultimate point of reference. The dawn of the modern age threw men back upon themselves. From Dubito ergo sum, "I doubt, therefore I am," came Cogito ergo sum, "I think, therefore I am."”

“Hannah Arendt, one of the twentieth century's most celebrated thinkers, sharply articulated this uncomfortable, straddled position in The Human Condition: "The great strides of Galileo proved that both the worst fear of human speculation-that our senses might betray us—and its most presumptuous hope–the Archimedean wish for a point outside from which to unlock universal knowledge–could only come true together."”

“Now while the ontological status of the physical laws hardly matters in the controlled environment of laboratories, it explodes in our faces when we ponder their deeper origin—let alone when we inquire about their biophilic character.”

“Anticipating Stephen, I responded emphatically: A God's-eye view is obviously fallacious in cosmology. We are within the universe, not somehow outside it. Stephen assented and concentrated intensely on composing his next phrase. The failure to recognize this, he clicked, has led us into a blind alley. We need a new philosophy [of physics] for cosmology. Ah, I laughed, time for philosophy at last!”

“We had this old idea, that there was a universe out there, and here is man, the observer, safely protected from the universe by a six-inch slab of plate glass. Now we learn from the quantum world that even to ob-serve so minuscule an object as an electron we have to shatter the plate glass; we have to reach in there...” -John Archibald Wheeler

“The sheer vastness of the possibilities in biological evolution means that any kind of causal deterministic explanation of why we have this particular tree of life is doomed to fail. This is why biologists work ex post facto, describing how a given outcome leads back to a specific sequence of branchings.”

“anthropic multiverse cosmology says, we have intrinsically biofriendly laws of physics merely because we could hardly have evolved in a universe where the physical conditions preclude our existence. In a sense the anthropic principle says that we find the physics of the observable universe the way it is because we are here.”

“quantum jitters…of spacetime create a self-reinforcing cycle of ever more frantic jittering that destroys its own basic structure. And unlike other fields, which undulate in a fixed background of space and time, gravity is spacetime. This is the crux of the difficulty when trying to reconcile gravity with quantum theory.”

“life built its stupendous complexity on an inconceivably large number of frozen accidents… From the functionalities of individual organisms over the characteristics of species to the taxonomy of the tree of life, law-like patterns in biology encode the outcomes of countless chance events, which, over a period of billions of years, in a co-evolving environment, have enabled layer upon layer of complexity to emerge”

“The observed universe contains about 10^50 tons of matter but almost no antimatter. This is another of its biofriendly properties, for if the expanding universe had emerged with equal amounts of each, then all particles would have quickly annihilated with their antiparticles, leaving behind a burst of high-energy gamma radiation and no matter at all. Yet when the LHC…creates exactly the same quantity of antimatter.”

“the Standard Model doesn't account for the dark matter that makes up 25 percent of the total mass and energy in today's universe and that may well involve many more species of particles and forces. Finally, the Standard Model leaves out dark energy and gravity, the warping of spacetime.”

“you can describe the behavior of a bundle of protons and neutrons at energies below a giga electron volt with a simplified particle theory that ignores that they are made up of trios of quarks. Much of the success of physics in the past has relied on this neat separation of scales. It serves as a warning... for the degree of trouble we're getting into when we attempt to include gravity in a unified framework...”

“It is remarkable that we can discover and use effective laws in particle physics without worrying or even knowing what's happening at shorter distances and higher energies...nature's hierarchical, nested structure has played out impeccably. You can...describe the macroscopic behavior of water with a hydrodynamic equation that models it as a smooth fluid, glossing over the complicated dynamics of its H₂O molecules.”

“It tells us that in the very earliest stages of cosmic expansion some of the basic structure of the physical laws co-evolved with the universe they governed. Physicists say that the familiar laws of particle physics are effectively laws-rules that hold only in the relatively low-energy and low-temperature environment that emerged a little while into the expansion.”

“So the picture suggested by the Standard Model of particle physics, applied in the melting pot of the hot big bang, is that the universe wasn't born with the values of the particle masses and force strengths that we have today. Instead these are properties of a broken-symmetry state that only congealed when the universe expanded and cooled.”

“A lightweight Higgs is important, however, for if the Higgs were much heavier, protons and neutrons would be heavier, too, far too heavy to form atoms. The unbearable lightness of the Higgs is yet another property that makes our universe propitiously fit for life.”

“Much like the discovery of dark energy in cosmology, the experimental discovery of the Brout-Englert-Higgs boson shows once again that empty space is not empty but filled with invisible fields, one of which is responsible for the mass of the matter that makes up almost everything we encounter in daily life.”

“Now, while photons are massless, just like gravitons conveying gravity, the bosons responsible for the weak and strong nuclear forces are very heavy. This is why the nuclear forces are short-range forces that operate only on the microscopic scales of atomic nuclei... It is the masslessness of their microscopic quanta that makes electromagnetism and gravity reach across the universe.”

“According to the Standard Model, matter particles like electrons and quarks are nothing but local excitations of extended fields. Particle-like excitations of the force fields that act between matter particles are known as exchange particles or bosons. Photons, for example, the exchange particles mediating the electromagnetic force, are the individual particle-like quanta of the electromagnetic force field.”

“All visible matter and the three particle forces that govern its interactions are bundled together in a tight theoretical framework: the Standard Model of particle physics. Developed in the 1960s and early 1970s, the Standard Model is a quantum theory that describes matter particles as well as forces in terms of fields, the undulating substances spread out in space that we have encountered before.”