Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Space-Time Compactification, Non-Singular Black Holes, Wormholes and
  Braneworlds via Lightlike Branes   We describe a concise general scheme for constructing solutions of
Einstein-Maxwell-Kalb-Ramond gravity-matter system in bulk space-time
interacting self-consistently with one or more (widely separated)
codimension-one electrically charged lightlike branes. The lightlike brane
dynamics is explicitly given by manifestly reparametrization invariant
world-volume actions. We present several explicit classes of solutions with
different physical interpretation as wormhole-like space-times with one, two or
more "throats", singularity-free black holes, brane worlds and space-times
undergoing a sequence of spontaneous compactification-decompactification
transitions.

15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
1
The categories of this paper are: cs
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
4
The categories of this paper are: cond-mat
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
6
The categories of this paper are: astro-ph
29
The categories of this paper are: funct-an