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Unformatted text preview: ss stars die? Supernova!
But what about the afterlife? We are now entering Chapter 13
“The Bizarre Stellar Graveyard”
For low mass stars the story is simple Final Phase (Nebula) Heavy, inert core
Star expands, expels outer layer Final State -- White Dwarf Remnant core (white dwarf)
Degeneracy pressure stabilizes
them against gravity White dwarfs cool over time White dwarfs -- the end state of low mass stars Speed required to escape their
surface --That’s fast!!!! Higher mass, even smaller radius! How massive can they be? The Chandrasekhar Limit
Quantum Mechanics requires
electrons to move faster the
more they are squeezed
As a white dwarf’s mass
approaches 1.4 Msun, this
requires electrons to move
faster than the speed of
light! S. Chandrasekhar (1910 - 1995) Not allowed!!!! So no white dwarf more
massive than 1.4 Msun What did you just say?
Nothing travels fast than the speed of light Quantum Mechanics:
The more electrons are conﬁned, the
faster they must move Both of these are required to
understand white dwarfs! 186,000 miles p...
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- Spring '08