Imagine a 2.2 sol mass neutron star on the brink of collapse with a radius of 12 km, an average density of 0.605e17 kg/m^3 and an average EOS of ~1/7. Based on active mass (i.e. including for pressure), the stress-energy tensor (g) would be based on [itex]g=\rho c^2+3P[/itex] resulting in g≡3.143 sol.(adsbygoogle = window.adsbygoogle || []).push({});

The neutron star goes quark-nova, throwing off ~0.6 sol mass of matter and reducing to 1.6 sol with a radius of 9 km, an average density of 1.042e18 kg/m^3 and an average equation of state of ~1/8 (though density increases, pressure appears to drop once neutrons breaking down into smaller components, i.e. quarks, hence a marginally lower EOS). Based on active mass, the stress-energy tensor for the quark star is now g≡2.2 sol.

Allowing for the mass thrown off, this makes a difference between the ns stress-energy tensor and the qs stress-energy tensor of ≡0.343 sol. Allowing for the fact that the expelled matter may carry some of this away as kinetic energy (roughly ≡0.168 sol mass) still leaves 0.175 sol mass of stress-energy 'unaccounted' for. Is it possible this could result in a gravity wave? Where exactly does the stress-energy induced by pressure come from?

source for neutron and quark star specifics-

'Neutron star interiors and the equation of state of super dense matter' by F. Weber, R. Negreiros, P. Rosenfield

http://arxiv.org/PS_cache/arxiv/pdf/0705/0705.2708v2.pdf page 3

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# Stress-energy tensor and active mass

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