Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Horava-Lifshitz gravity, absolute time, and objective particles in
  curved space   Recently, Horava formulated a renormalizable theory of quantum gravity that
reduces to general relativity at large distances but violates Lorentz
invariance at small distances. The absolute time involved in this theory allows
to define an objective notion of particles associated with quantization of
fields in classical gravitational backgrounds. The Unruh effect and other
observer-dependent notions of particles in curved space are interpreted as
effects caused by interaction between the objective vacuum and the measuring
apparatus made up of objective particles.

23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex