2 ms·
Something doesn't add up, obviously. For one thing, squeezing the sphere smaller against pressure requires work. That's an external energy input. The system is
by kazinator 2y ago
Something doesn't add up, obviously.
For one thing, squeezing the sphere smaller against pressure requires work. That's an external energy input. The system is not closed if some agent is available that can squeeze the sphere smaller.
- hoseja 2y agoIt's not getting squeezed, it's just gravitationally collapsing. The same thing happens when forming stars, except obviously there's all the electromagnetic repulsion, then nuclear repulsion, then black hole formation. The article speaking about "stars" as analogy for pointlike masses is kinda misleading. If it talked instead about gas in a nebula forming into a hot star, it would make much more sense.
- kazinator 2y agoIn this gedanken experiment, the stars are placed into a spherical container. Particles within this container bounce off its walls. It is like a cylinder full of gas. The container does not collapse with the stars; its dimensions are somehow controlled by the experimenter. Well, if there is pressure inside this sphere, then you cannot shrink it without working against the pressure, and doing so will add energy into the system because work is being done on it.