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wolram
May27-04, 02:02 PM
neutron stars seem an oddity to me, they seem to have
to much mass to size to be held together purly by gravity
do neutrons have mutual attraction? or is space very very
distorted by them?

jcsd
May27-04, 02:09 PM
They ARE held togethr by garvity, you can never have enough mass to volume to be held together by gravity.

wolram
May27-04, 05:07 PM
They ARE held togethr by garvity, you can never have enough mass to volume to be held together by gravity.
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so how does a neutron star become a neutron star, it seems that
size for size the neutron star should distort space time in the most
extreem way, probabaly more tightly than a black hole.

jcsd
May27-04, 05:22 PM
They ARE held togethr by garvity, you can never have enough mass to volume to be held together by gravity.
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so how does a neutron star become a neutron star, it seems that
size for size the neutron star should distort space time in the most
extreem way, probabaly more tightly than a black hole.

A neutron star becomes a neutron star via stellar collapse when the stellar remnants have enough gravity to overcome the degenarcy pressure between electrons and protons after the star goes supernova. What stops it becoming a black hole is that it doesn't have enough gravity to overcome the degenracy pressure between neutrons.

Labguy
May27-04, 07:26 PM
This answers most of the basic questions:
http://www.astro.umd.edu/~miller/nstar.html#formation

wolram
May28-04, 03:37 AM
I had a look on google as i wasn't sure about the explanations
given, and found this,

http://xxx.arxiv.cornell.edu/abs/astro-ph/0311471

Neutron stars without gravity
Authors: V.K.Ignatovich

It is demonstrated that not only gravity, but also neutron-striction forces due to optical potential created by coherent elastic neutron-neutron scattering can hold a neutron star together. The latter forces can be stronger than gravitational ones. The effect of these forces on mass, radius and composition of the neutron star is estimated.

this maybe speculative but it does show that gravity may not be the
only contributer to the binding force of a neutron star.

TeV
May28-04, 11:52 AM
What stops it becoming a black hole is that it doesn't have enough gravity to overcome the degenracy pressure between neutrons.+ there's is often rotation..

Labguy
May28-04, 12:01 PM
A neutron star becomes a neutron star via stellar collapse when the stellar remnants have enough gravity to overcome the degenarcy pressure between electrons and protons after the star goes supernova. What stops it becoming a black hole is that it doesn't have enough gravity to overcome the degenracy pressure between neutrons. At this level, it would be degeneracy pressure of the strong nuclear force; binding force between the quarks that make up the neutrons.