swansont

How much cycles will you get per night? Now, imagine running a heat engine at a higher temperature (i.e. at 373K instead of 273), and using the same heat sink. What happens to the efficiency?

Right. Which means the energy would be better put to use on a more efficient device.

Nothing has a speed that exceeds c. Expansion is not a speed as we normally discuss speed.

Until that becomes "all" then you can't really disagree. Some people will inevitably want more, and that's why the system fails.

Put a few kg of mass on top and see if that's still true. Well, it's a heat engine, so yeah. You convert some small fraction of the heat into work. In this case probably a very small fraction, since efficiency depends on the temperatures involved.

Hawking radiation won't leave at lightspeed, unless it's a photon. JC didn't say anything about a fusion reactor, he just said that you'd need to get the gas bery hot to get to that speed. No, it doesn't result in that.

They're part of human nature, so they are inevitable, and why nobody has gotten communism to work. It's never true communism. You end up at Orwell's "All animals are equal but some are more equal than others"

Then you can make inquiries and learn the technical limitations. Radioactive decay does not get you the power for this to be a viable energy source. It's got to be an actual perspective and not a fanciful illusion.

Yep. Higher income means different expectations and different worries, which are largely self-generated. You have the money and now you want a bigger house, a swimming pool, nicer (and possibly more) cars, kids in private schools. None of which is driven by need, but by expectations of self and society. Keeping up with the Joneses. And you can also end up with nothing saved up for retirement, because you spent so much on transient goods.

If you, and everyone else, are provided with your needs, then no actual money is required. The issue I think you are describing is driven by wealth inequality, which is (in principle) eliminated.

The mean free path is still the same, at the point you pop the container. Anyway, the relevant question is whether the thermal energy is comparable to the mass energy of one of the molecules, under the assumption that all of the thermal energy goes into one particle. If that's not the case, then there's not enough energy to get close to c. k is 8.6 x 10^-5 eV/K if T is 300K, then kT is ~ 0.026 eV You need ~ 1 GeV for each nucleon, to give you a KE equal to the mass energy (which would imply a gamma of a tad more than 2, which is v = 0.866c) So there will be a certain number of atoms where this will hold (around 10^11, so much, much less than a mole). You just then need the improbable circumstance where one particle has all the KE, and doesn't collide before escaping. But that's not really what the question was - it wasn't one particle going near lightspeed. John Cuthber's treatment is the way to go. And I'm still trying to figure out why escape velocity matters (or dark matter, for that matter. Space expansion doesn't give you a local velocity)

You're missing the point. If you have a containment vessel, the air pressure is irrelevant. It's how you can have vacuum chambers. The outside pressure, on the exterior walls is atmosphere, but the interior pressure is very small (essentially zero) because your chamber (steel, aluminum, titanium, whatever, but not probably paper) is rigid, and can withstand a pressure differential. So water in a tube can be exposed to the actual atmosphere on only one side. There will be pressure exerted by the vessel, and the value may be 1 atm of pressure, but it will not be the atmosphere that exerts it. No, the containment vessel will exert 1 atm on the water before you add the weight. In the water, everything is at 1 atm. (ignoring height effects for the moment). If the water exerts 1 atm, the containment vessel had better be exerting 1 atm back at it, if you are in steady state. If you take a vessel not designed to withstand the pressure, then sure, it is likely to fail. Way to cherry pick an example. It's like trying to demonstrate that flight is impossible by throwing a rock. OTOH, I have used vacuum systems, and they don't crumple. Been on a submarine, too, and survived being under several atmospheres of pressure differential. The notable part being these are devices designed specifically for the task, which a barrel (designed to hold liquid in) is not. Yes, we call it ice.

The best things in life are free But you can give them to the birds and bees Just give me money. That's what I want. Seriously, though, what's the alternative? Barter? Actual communism?

That's a poor argument, as it rests upon the fact that paper has poor structural integrity; you tend to not make piston systems out of paper, because you want/need the system to be rigid. If you had a rigid, non-permeable cup, you could evacuate the region around the sides and bottom, and the water isn't going to notice.

You had been talking about a piston, which would be exposed to atmosphere on one side, so it's ~132 lbs. (and an additional 50 lbs would not be insignificant) If you think 6 sides are exposed, you'd have to wonder how the water maintains its cubic shape before it freezes, under atmospheric pressure.

Yes. Time isn't an object or substance, or anything that has momentum or energy. It doesn't travel a physical path.

How so? 14.7 psi x 9 si = 132.3 lbs

It's a continual process, and some of the effects have many layers of Feynman diagrams, with multiple loop structures even at the first layers (they tend to get much more complex as you go to more loops), so I don't think you can narrow it down to just the recombination. The whole process is responsible for the contribution, AFAIK. The application of conservation laws at the nodes is bookkeeping. Plus, I don't know that there would be any way to test this hypothesis

As long as you can avoid collisions, which is difficult. The mean free path of air molecules at room temperature is of order 100 nm. And escape velocity is << c

Light bending around a massive object is predicted by the theory, as is the frequency shift of light as it climbs up or drops down a gravitational well. It doesn't have to "consider" EM, since the effects are, in a sense, orthogonal. i.e. the nature of the interaction doesn't matter. For E=mc^2, the mass of a system decreases when its energy is reduced, regardless of whether the interaction is electromagnetic or nuclear. Much like how F=ma doesn't have to specify what kind of force is involved.

I think the problem here is the definition of "exist" which was not provided. The explanation of the Casimir effect that invokes virtual particles uses Feynman diagrams In both of these cases, the answer is clearer if the question were "do virtual particles have a measurable effect" because in both cases, they obviously do, and for physics, that's enough.

SFN defines it a particular way. Then let’s see the model and the support.

Any non-mainstream proposal is speculation here. And someone with your claimed background should know what science means by “a theory”

“Circumstances” that have an impact that we can model and test. As with other “circumstances” that occur in other parts of physics (e.g. symmetries that give rise to conservation laws, circumstances of a lack of acceleration of a frame that gives rise to Newton’s laws, etc.) Relativity doesn’t care. We’ve tested it on macro “circumstances” and it keeps passing the tests.

No. And scientists are not engineers. The plural of anecdote is anecdotes. Not data. The best you can do here is confirm that a scientific background doesn’t prevent you from getting rich. Science background. But not work as scientists, as CharonY notes.