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There's a bunch of ways to think of this. But the most immediate one is simply that your formula for circular orbital velocity is wrong. You might have expected it to be correct because the Newtonian formula for the escape velocity happens to be right, but that's peculiarity of the niceness of the S...

Hence primarily. My point is that the predominant term of entropy in macroscopic situations is going to be the heat and energy distribution, so it shouldn't be at all surprising that the "entropy" of rocks goes up if you exclude heat and energy distribution, because you are then excluding...

If there was exactly zero vacuum energy, this would be less provocative a mystery than for there to be 'some but only a tiny amount,' because all the models that predict it should exist at all predict that it should be extremely large, correct? It would be less provocative a mystery, yes, in that p...

In a Big Crunch scenario, the smooth FRW cosmology is an over-idealization. A collapse would be a very inhomogeneous process. For example, lots of black holes should form here and there, and black holes maximize entropy for their size. Therefore, it is inappropriate to think of the Big Crunch singul...

I was thinking the proton charge radius, but the main reason I didn't include it was that the problem is far more likely to lie in QCD than QED, whereas with the muon magnetic moment QED would still be the predominant contribution, so differences in that are more likely. But yeah, again this falls ...

The discovery of superconductors is a bad analogy for several reasons, foremost of which is that nothing in electromagnetism suggested that they're impossible in the first place. Rather, before actual superconductors were discovered, hypothetical ones have been used as toy models or in illustration ...

Ah, you're right! I did misunderstand why it's presented in the way it is. I was so used to non-local models being discounted as unphysical that I missed part of an important point of this paper: the Bell-analogue inequality (1) in their paper would also restrict non-local models of QM. (Spekkens' m...

I don't even entirely understand exactly what is meant by the concept of the wave function being "real" or not. ... It just feels weird to me to talk about the wave function in terms of being "real" or not, as opposed to talking about it in terms of how well its assumptions alig...

That's not what the paper actually establishes. What they're ruling out is a hidden-variable theory that says that the wavefunction represents a state of partial knowledge about some underlying reality. The experiment supports the proposition that there is no underlying reality that the wavefunction...

Take a cone and superpose all plane waves that travel in directions perpendicular to the surface of said cone, all with same amplitude and phase. The result is a Bessel beam, which is axially symmetric and propagates along the axis of the original cone. Since it's formed by superposition of plane wa...

In (relativistic) quantum field theory, the Poincaré group defines the notion of "particle", because this is the symmetry group of special relativity: translations, rotations, Lorentz boosts. This ensures that their existence can be unambiguously defined in an invariant way. The Poincaré g...

They are not fermions either. They have spin-1/2, so some people call them fermions, but that's not actually accurate. That there only two kinds of statistics for indistinguishable particles, Bose-Einstein and Fermi-Dirac, depends on several things, including the fact that SO(3), the special orthogo...

#3 is simply wrong. The 'full report' does not describe "tests in which turbo pumps were used to evacuate the test chamber to a pressure of five millionth of a Torr". Rather, it describes the calibration procedure, which was done in a vacuum. The tests were not done in a vacuum, and the re...

Hey, Kuroneko. Most of what you (ever) said is over my head, but I was wondering if you could clarify this: "inertial frames are only ever local: over non-infinitesimal regions, they are approximations correct only to first order ." Everything here is continuous. What I mean is that (a) i...

If one takes the comment step by step, it makes no sense at all. At best it's based on the writer's entirely private mental pictures that appear to be quite disconnected from actual physics. For example, even the first sentence: If this space is relativistic, ... What does that mean? [then] the spee...

When, if ever, are they going to test the EmDrive in a vacuum? The Chinese didn't do it, now a NASA lab doesn't do it. By the way, calling the EmDrive "relativity-based" is completely ludicrous. The author bases his idea on the notion that special relativity requires that "separate fr...

The entire point of the Schrödinger's cat paradox is to demonstrate the difficulty in separating quantum systems (radioactive decay) with classical ones (cats). That's not correct. Following the description of setup of the thought experiment, Schrödinger wrote: It is typical of these cases that an ...

You're obviously more well-versed in quantum mechanics than I am, but even I know that your interpretation is certainly controversial. I'm claiming that quantum states describe probabilities, which is about as mainstream as it gets. (It should be emphasized Einstein's "spooky action at a dista...

I should probably give some explicit references for the above. Brief background: quantum mechanics is due to the work of a great number of people, but the person most responsible for its mathematical formalization in terms of Hilbert spaces is von Neumann, most relevantly here including the treateme...

Again, I understand your position - but I'm a bit baffled how you're comfortable completely ignoring the singularly defining feature of wave function collapse when comparing it to the collapse of a standard, classical probability distribution. I'm not ignoring it. Quite the opposite: I'm saying it'...

People tend to mystify QM to such degree... Still, I'm not certain if the shoe analogy really works. No analogy is perfect, of course, but if wave function collapse is analogous to Alice opening the box and looking at the shoe, the analogy breaks down in the sense that an actual left shoe or right s...

I'm not sure I understand your question. Pick an arbitrary direction in space, which we'll call the z-axis. If you measure the electron spin along this axis with some measurement device**, sometimes you'll get spin-up and sometimes you get spin-down. If you select just the spin-up ones and throw awa...

Can you elaborate a bit on why the "popular interpretation", at least, of quantum entanglement seems to contradict what you're saying? Most laymen call to mind Einstein's "spooky action at a distance" when thinking of quantum entanglement, and the popular literature on it claims...

If something like a "quantum Internet" is actually possible via exploiting quantum entanglement to send information, then the ramifications are truly insane. It would mean we could have instant communication across interstellar distances. It doesn't mean any such thing. Quantum entangleme...

Anyway, we all agree that energy CAN be turned into mass. Only as a crude analogy. If the photon has energy E in the rest frame of the nucleus (mass M), then the combined photon+nucleus system has mass m = √((M+E)²-E²) = M√(1+2E/M). So you're not turning energy into mass, because all the mass is al...