Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The trans-Planckian problem as a guiding principle   We use the avoidance of the trans-Planckian problem of Hawking radiation as a
guiding principle in searching for a compelling scenario for the evaporation of
black holes or black-hole-like objects. We argue that there exist only three
possible scenarios, depending on whether the classical notion of long-lived
horizon is preserved by high-energy physics and on whether the dark and compact
astrophysical objects that we observe have long-lived horizons in the first
place. Along the way, we find that (i) a theory with high-energy superluminal
signalling and a long-lived trapping horizon would be extremely unstable in
astrophysical terms and that (ii) stellar pulsations of objects hovering right
outside but extremely close to their gravitational radius can result in a
mechanism for Hawking-like emission.

20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int