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[探索发现] 2015-04-17 BBC:星光七纪元-26

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That’s why what we physicists call pressure.
This pressure is created as the particles jostle for position, it’s a principal of quantum mechanics, and when it was applied to stars, the lives of dead white dwarfs suddenly made sense. What stop them collapsing completely was the gravity was resisted by the pressure generated between particles themselves.
You know white dwarf, you got a delicate balance between the gravity which try to squeeze together and the pressure of these electrons trying not all have their dresses in the same place that try to push out and it’s a balance between these gravity pulling in and electrons pushing out that keeps the white dwarf the size it is.
It’s also what let’s a star with no fuel supply, shinning for billions of years.
These white dwarfs also are very small, so they got a very small surface area which means although their white hot, the light they emit, the heat energy which they send out is still very limited just the very small size of the surface, now carries on radiating light and it gradually cools down, it gradually gets dimmer and dimmer, it’s a little bit like a retired person sitting in an old star’s home, it’s still you know ticking along, but it gradually gets slower and slower, dimmer and dimmer, there are white dwarfs cluttering up our galaxy, or the other galaxy
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