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arXiv · 0905.4425

Horizons in matter: black hole hair vs. Null Big Bang

K. A. Bronnikov·O. B. Zaslavskii
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Abstract

It is shown that only particular kinds of matter (in terms of the "radial" pressure to density ratio $w$) can coexist with Killing horizons in black-hole or cosmological space-times. Thus, for arbitrary (not necessarily spherically symmetric) static black holes, admissible are vacuum matter ($w=-1$, i.e., the cosmological constant or some its generalization) and matter with certain values of $w$ between 0 and -1, in particular, a gas of disordered cosmic strings ($w=-1/3$). If the cosmological evolution starts from a horizon (the so-called Null Big Bang scenarios), this horizon can co-exist with vacuum matter and certain kinds of phantom matter with $w\geq -3$. It is concluded that normal matter in such scenarios is entirely created from vacuum.

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K. A. Bronnikov, O. B. Zaslavskii. 2009-05-27. Horizons in matter: black hole hair vs. Null Big Bang. https://doi.org/10.1142/s0218271809015898

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