Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fermionic microstates within Painlev\'e-Gullstrand black hole   We consider the quantum vacuum of fermionic field in the presence of a
black-hole background as a possible candidate for the stabilized black hole.
The stable vacuum state (as well as thermal equilibrium states with arbitrary
temperature) can exist if we use the Painlev\'e-Gullstrand description of the
black hole, and the superluminal dispersion of the particle spectrum at high
energy, which is introduced in the free-falling frame. Such choice is inspired
by the analogy between the quantum vacuum and the ground state of quantum
liquid, in which the event horizon for the low-energy fermionic quasiparticles
also can arise. The quantum vacuum is characterized by the Fermi surface, which
appears behind the event horizon. We do not consider the back reaction, and
thus there is no guarantee that the stable black hole exists. But if it does
exist, the Fermi surface behind the horizon would be the necessary attribute of
its vacuum state. We also consider exact discrete spectrum of fermions inside
the horizon which allows us to discuss the problem of fermion zero modes.

24
The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org