Rotational terms and quantum degeneracy in black holes

TL;DR

This paper argues that the first law of black-hole mechanics has direct physical meaning, interpreting all terms as rotational kinetic energy, and reveals degeneracy related to internal angular momentum distribution.

Contribution

It provides a new physical interpretation of the first law of black-hole mechanics, emphasizing the rotational kinetic energy aspect and analyzing degeneracy in black hole internal angular momentum.

Findings

All terms in the first law have the same mechanical meaning as rotational kinetic energy.

The Kerr-Newman black hole can be viewed as a system of non-degenerate plane rotators.

Degeneracy arises from the energy independence on the internal angular momentum location.

Abstract

It is believed that the first law of black-hole mechanics has no independent physical significance and acquires it only after identifying with the first law of thermodynamics. It is argued here that the first law of black-hole mechanics has a direct physical significance: not only the term $\Omega dJ$ but all its terms have the same mechanical meaning - the rotational kinetic energy of a black hole in real or in an internal space. Moreover, it is shown that the Kerr-Newman black hole is a system of non-degenerate plane rotators represented by the corresponding terms in the first law of black-hole mechanics. It is found that a degeneracy arises because the energy of a black hole does not depend on where an internal angular momentum of a black hole associated with the black hole area is determined on the horizon.