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swansont

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Everything posted by swansont

  1. That wasn't the premise. The premise was that there are people on the police force predisposed to use violence/excessive force. On what do you base this?
  2. You added a partition, where there was none. You added a piston earlier, and talked about changing variables that were fixed, and doing work. You’ve done little but change the conditions.
  3. A rotating body is more massive than an otherwise identical non-rotating body.
  4. No, you don’t get to change the conditions of the example. It’s an ideal system. You keep ignoring that. Even if it isn’t, fine. If we’re at STP and have one mole of gas, so the volume of the container is 22.4L. The ideal gas has a mass of, say, 10 grams. The container is just under 30 cm a side and has a mass of, say, a kg. You have your momentum transfer, so the container can shift a small amount if needed. How are those violated? Action/reaction arises from force. Arrival, departure, etc. are not force. Nothing external. It’s all internal. That’s not how gases behave. It’s not a 1-for-1 matchup. You could have 10 moving right with 1 unit of momentum and 1 moving left with 10 units, and momentum is zero. So you agree you don’t need the atoms to have their momentum cancel Why are small fluctuations OK, but larger ones require work?
  5. You need to clarify what constitutes an explosion. Is one fission inducing another enough? How many steps of a chain reaction are enough? Part of the limit on size would have to be from ensuring the reactions take place, rather than the neutrons just leaking out and rapidly going subcritical. You could make it smaller than was demonstrated, but it might not actually explode reliably.
  6. There is no change in P, V or T ? This was never part of what I had been discussing. I wasn’t aware you were waiting for me to address it. With one ball it’s not a problem, though. So the number of particles is equal in each octant? What if there are an odd number of particles? You said 42 before I brought this argument up. I hope causality isn’t under attack here, too. 42 isn’t divisible by 8. Let’s make it 48 - 6 particles per octant. Why can’t that number change? Why can’t there be 7 in one octant, and 5 in another? What prevents that? It’s not momentum. They travel at different speeds, and there’s a finite transit time.
  7. Yes. I didn’t introduce “single observer bias” “agenda” is offensive? You’re the one who stated a plan, not included in the OP. But there is no compression, and no heat flow. The entropy hasn’t fallen. AFAIK they’re wrong about that. Will you now, finally, address the outstanding questions: What is the mechanism that prevents more balls being on one side of the box*? At what value of N does the mechanism manifest itself? *This is a big issue, because if we have symmetry, I can draw this line along any axis. If it can’t happen, then doesn’t the number in each octant have to be constant? If it’s not, then some half has more than the other
  8. It seems the answer is “no” Apparently it’s a slogan and not an obligation.
  9. These are two separate issues. One does not follow from the other (emphasis added) The courts have ruled that this is not the case in the US https://mises.org/power-market/police-have-no-duty-protect-you-federal-court-affirms-yet-again They can back off and let you be attacked, and they are not being derelict in their duty. According to the law/courts. If someone is predisposed to using violence, giving them more tools to do violence won’t result in more violence? Interesting take.
  10. I don’t have sufficient familiarity with the physics to have an opinion.
  11. You had specifically focused on the CoM of the gas. You went out of your way to point this out. An observer traveling with the ball isn't really a viable approach, knowing full well we are going to move on to multiple balls, because we’ve already done this. Plus the view prior to this was an observer in the lab frame. You seem reticent to answer the question, which is quite obviously “no, the CoM of a single ball is not fixed” Indeed. One wonders what the point of introducing it was. Yes, of course, all if this posturing suggested an agenda. This “next stage” will be in a new topic, right? Can we get back to the discussion at hand? Belief is not a physics argument. It is obviously possible when N is small. What mechanism makes it impossible when N is large?
  12. Explain the CoM problem for one ball in my example. Is the CoM fixed?
  13. You haven’t provided the source (i.e. document/transcript)/ context of the quote.
  14. When m goes to infinity, the mass of the gas is irrelevant. The CoM will be the same, no matter what happens to the gas. It’s a non-issue for this explanation
  15. The collisions are elastic and the box mass is infinite. Ideal system, remember? If there is no displacement, there is no work. These collisions would increase, not decrease, the volume of the box, so no.
  16. When the ball is traveling, the CoM is moving, so this isn’t necessarily a constraint but it’s an idealized system (we start with an ideal gas) so the container has a mass >> the mass of the gas. Effectively infinite mass. edit: xpost with Ghideon
  17. V doesn’t change. No, that does not follow Start with one ball, with some energy E, under the conditions of an ideal gas, in some box with rigid walls. Obviously, it can be anywhere in the box. Same thing for two. Wile they will occasionally collide and exchange energy and momentum, there is no mechanism that requires one ball be on each side. Two balls being on one side does not require a change in volume. Three balls, four balls - still no mechanism. Any conclusion about their average position is statistical. It’s like a coin toss of multiple coins - it becomes less likely to get all heads, or all tails, but nothing prevents it. Now increase it to an arbitrary number N. At what point does a mechanism manifest that prevents all the balls being on one side? What is that mechanism?
  18. The piston was your introduction - which violates the conditions of the problem - so this clarifies nothing.
  19. You can point to unpredicted benefits from past scientific discovery.
  20. A piston means V isn’t constant. position ≠ momentum Why does it break these laws? It’s not a low entropy condition, as such. Did they say that, or is that your interpretation? Saying that doesn’t make it true. How does this allow a jump to absolute zero?
  21. ! Moderator Note Details should be posted here. Posting to advertise a site is against the rules. ! Moderator Note Those are all questions that can be asked without prefacing it with mentioning youtube, or physics-free claims. Try again, if you can comply with the rules
  22. What does equilibrium mean in terms of a gas? So the parameters are not well-defined in that situation - they can show large deviations. Also note I responded to your question about the 2nd law being statistical, not the OP. The “small number” as applied to the OP is fabricated You did, though. Your gas became regularly-spaced, with no relative motion. It’s true there’s no path to get to that state, but AFAIK, nobody is claiming that state exists They are not “representative” if the videos you are decrying do not use them. You are trying to use a response to one very specific question and apply it to a broader question, which does not necessarily share the same assumptions. Do you want to discuss the issue you brought up in the OP, fine - do that. You want to discuss issues arising in stat mech, fine - open a new thread and do that. Don’t mix them.
  23. There is no such thing as touching when you get to the atomic level. Electrons repel each other, so at best atoms are close to each other, but quantum mechanics means the boundary of an atom isn’t well-defined. Surfaces are not infinitely flat, so there will be other atoms/molecules in there.
  24. Who said they were non-equilibrium? You didn’t indicate N=42 before, and regularly-spaced is a new addition, as well as zero relative motion. Where did these come from? You can’t go changing the parameters like that. Wikipedia articles like this are more like a textbook, but there’s more in the link. Not sure why you are thinking the system is low entropy.
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