QuarkyMeson's latest activity
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QuarkyMeson replied to the thread Graduate Is the 2-qubit singlet state invariant under bilateral projections?.I mean, just so you know I agree with you. I don't think span preservation for quantum states is a good definition of invariance. The 0... -
QuarkyMeson reacted to PeterDonis's post in the thread Graduate Wavefunction in the context of quantum physics with
Like.
Yes. Yes. Both of these functions will be square integrable functions of one variable, so they are both elements of Hilbert spaces... -
QuarkyMeson replied to the thread Alien life, probabilities, and interstellar propagation of human life.Yeah, see Scotts post here for more information: Given a finite volume and finite amount of energy there are only a finite number of...
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QuarkyMeson reacted to .Scott's post in the thread Alien life, probabilities, and interstellar propagation of human life with Like.
A couple of comments: First, you presume an infinite universe but you call out "observable universe" - which may not be infinite...
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QuarkyMeson reacted to PeroK's post in the thread Alien life, probabilities, and interstellar propagation of human life with Like.
That's true in the mathematical model of an infinite universe. The question is how relevant that is. We may never be certain that the...
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QuarkyMeson replied to the thread Alien life, probabilities, and interstellar propagation of human life.Yes, a big caveat to all this is that the universe is truly infinite and that energy is also randomly and uniformly distributed. It...
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QuarkyMeson replied to the thread Alien life, probabilities, and interstellar propagation of human life.If the universe is infinite and matter is distributed randomly and uniformly, patterns have to repeat. This is because there’s a limit...
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QuarkyMeson replied to the thread Undergrad Single vs. Double slit coherence clarification please.This is a misconception. When people say it's like a particle or wave it doesn't mean it's actually either. It's just in general...
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QuarkyMeson replied to the thread Space Stuff and Launch Info.I guess that makes sense. You already have engines and a fuel tank so the weight savings (if any) of adding in a parachute system...
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Parachutes don't give you precision, so you can only do an ocean splashdown. That's bad for the engines, and the corrosive salt water is...
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QuarkyMeson replied to the thread Graduate Is the 2-qubit singlet state invariant under bilateral projections?.In QM we can look at two different update rules: $$|\psi\rangle \mapsto U|\psi\rangle$$ with ##U## unitary. This evolution of the state...
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QuarkyMeson replied to the thread Undergrad Which-Path from Global Momentum Measurement in Double Slit.Like before, a global measurement of the screen’s total momentum gives which-path information only if the two recoil states are...
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QuarkyMeson replied to the thread Alien life, probabilities, and interstellar propagation of human life.The universe appears homogeneous and isotropic on large scales. The lower bound for the size of the universe is much much larger than...
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QuarkyMeson replied to the thread Undergrad Which-Path from Global Momentum Measurement in Double Slit.This is basically what you're asking: https://arxiv.org/pdf/cond-mat/0101157 A global momentum measurement of the screen only yields...
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QuarkyMeson replied to the thread Graduate Is the 2-qubit singlet state invariant under bilateral projections?.I mean, you just kind of make it up and pick a definition for it so everyone is on the same page. You could argue for exact invariances...