Something Deeply Hidden Quotes

“functions evolve, called Schrödinger’s equation. We can express Schrödinger’s equation in words as: “The rate of change of a wave function is proportional to the energy of the quantum system.” Slightly more specifically, a wave function can represent a number of different possible energies, and the Schrödinger equation says that high-energy parts of the wave function evolve rapidly, while low-energy parts evolve very slowly. Which makes sense, when we think about it. What matters for our purposes is simply that there is such an equation, one that predicts how wave functions evolve smoothly through time. That evolution is as predictable and inevitable as the way objects move according to Newton’s laws in classical mechanics. Nothing weird is happening yet.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“This cloud is often called a wave function, because it can oscillate like a wave, as the most probable measurement outcome changes over time. We usually denote a wave function by Ψ, the Greek letter Psi. For every possible measurement outcome, such as the position of the particle, the wave function assigns a specific number, called the amplitude associated with that outcome. The amplitude that a particle is at some position x0, for example, would be written Ψ(x0).”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“In principle, a vast intellect could know the state of literally every object in the universe, from which it could deduce everything that would happen in the future, as well as everything that had happened in the past. Laplace’s demon is a thought experiment, not a realistic project for an ambitious computer scientist, but the implications of the thought experiment are profound. Newtonian mechanics describes a deterministic, clockwork universe.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“The fundamental new element of quantum mechanics, the thing that makes it unequivocally distinct from its classical predecessor, centers on the question of what it means to measure something about a quantum system. What exactly a measurement is, and what happens when we measure something, and what this all tells us about what’s really happening behind the scenes: together, these questions constitute what’s called the measurement problem of quantum mechanics. There is absolutely no consensus within physics or philosophy on how to solve the measurement problem, although there are a number of promising ideas.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“The idea that “there’s something we don’t know,” given a certain wave function, is an outdated relic of our intuitive insistence that what we observe is what really exists. Quantum mechanics teaches us otherwise.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“That’s the uncertainty principle. It’s not that we can’t know both quantities at the same time; it’s just a fact about how wave functions work that if position is concentrated near some location, momentum is completely undetermined, and vice versa.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“Utterly wrong, according to the AQM way of thinking. It comes from a stubborn insistence on thinking of an electron as a tiny classical dot zipping around inside of the wave function, rather than the electron actually being the wave function.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“The best we can do is to predict the probability of seeing the electron in any particular location or with any particular velocity.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“The enigma at the heart of quantum reality can be summed up in a simple motto: what we see when we look at the world seems to be fundamentally different from what actually is.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“A police officer pulls over Werner Heisenberg for speeding.

"Do you know how fast you were going?" asks the cop.

"No," Heisenberg replies. "But I know exactly where I am."

I think we can all agree that physics jokes are the funniest jokes there are.”
― Sean Carroll, Something Deeply HIdden: Quantum Worlds and the Emergence of Spacetime

“As impressive as matrix mechanics was, it suffered from a severe marketing flaw. The mathematical formalism was highly abstract and difficult to understand. Einstein's reaction to the theory was typical: A veritable sorcerer's calculation. This is sufficiently ingenious and protected by its great complexity to be immune to any proof of its falsity.

This from the guy who had proposed describing space-time in terms of non-Euclidian geometry.”
― Sean Carroll, Something Deeply HIdden: Quantum Worlds and the Emergence of Spacetime

“If we pretend that the emission of gravitational waves were the only thing affecting the Earth’s orbit, it would take over 1023 years for it to crash into the sun. So perhaps the same thing is true for atoms: maybe electron orbits aren’t really stable, but they’re stable enough.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“If there were some nefarious conspiracy to make the world look quantum-mechanical, it had to have been set up hundreds of years ago, when the light left those stars. It's possible, but doesn't seem likely.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“Should the branching of our current selves into multiple future selves affect the choices we make? In the textbook view, there is a probability that one or another outcome happens when we observe a quantum system, while in Many-Worlds all outcomes happen, weighted by the amplitude squared of the wave function. Does the existence of all those extra worlds have implications for how we should act, personally or ethically? It’s not hard to imagine that it might, but upon careful consideration it turns out to matter much less than you might guess.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“The new feature of quantum mechanics is the duplication of that pattern when the wave function branches. That’s no reason to panic. We just have to adjust our notion of personal identity through time to account for a situation that we never had reason to contemplate over the millennia of pre-scientific human evolution.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“quantum mechanics has nothing to do with the question of free will.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“GRW can be thought of as Everettian quantum mechanics plus a random process that cuts off new branches of the wave function as they appear.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“this is what all thoughtful physicists should be talking about. What matters to me is not that everyone become an Everettian, but that people take the challenge of understanding quantum mechanics seriously. I’d much rather have a dialogue with someone who is a dedicated proponent of hidden variables, for example, than try to engage the interest of someone who just doesn’t care.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“the concept of a single person extending from birth to death was always just a useful approximation. The person you are right now is not exactly the same as the person you were a year ago, or even a second ago. Your atoms are in slightly different locations, and some of your atoms might have been exchanged for new ones.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“general relativity is a thoroughly classical theory, with analogues of position and momentum for the curvature of spacetime, and no limits on how we might measure them. Taking that theory and “quantizing” it, constructing a theory of wave functions of spacetime rather than particular classical spacetimes has proven difficult.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“Wheeler’s philosophy was that we should start prudently, with aspects of nature we believe we understand, and then act boldly, extrapolating our best ideas to the ends of the universe.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“talented graduate students, including future Nobel laureates such as Richard Feynman and Kip Thorne. One of those students was Hugh Everett III, who would introduce a dramatically new approach to thinking about the foundations of quantum mechanics.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“Entanglement arises because there is only one wave function for the entire universe,”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“A police officer pulls over Werner Heisenberg for speeding. “Do you know how fast you were going?” asks the cop. “No,” Heisenberg replies, “but I know exactly where I am!”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“In de Broglie’s view, his matter waves served to guide particles around, not to replace them entirely. (He later developed this idea into pilot-wave theory, which remains a viable approach to quantum foundations today, although it is not popular among working physicists.)”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“took more than ten years for a more complete framework, the “new quantum theory,” to finally come on the scene. In fact, two competing ideas were proposed at the time, matrix mechanics and wave mechanics,”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“Quantum mechanics ultimately unified particles and fields into a single entity, the wave function.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“An electron is in a superposition of every possible position we could see it in, and it doesn’t snap into any one”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“Atoms aren’t mostly empty space; they are described by wave functions that stretch throughout the extent of the atom.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime

“Our observations aren’t revealing pre-existing facts of which we were previously ignorant; at best, they reveal a tiny slice of a much bigger, fundamentally elusive reality.”
― Sean Carroll, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime