Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Compact extra-dimensions as solution to the strong CP problem   We show that the strong CP problem can, in principle, be solved dynamically
by adding extra-dimensions with compact topology. To this aim we consider a toy
model for QCD, which contains a vacuum angle and a strong CP like problem. We
further consider a higher dimensional theory, which has a trivial vacuum
structure and which reproduces the perturbative properties of the toy model in
the low-energy limit. In the weak coupling regime, where our computations are
valid, we show that the vacuum structure of the low-energy action is still
trivial and the strong CP problem is solved. No axion-like particle occur in
this setup and therefore it is not ruled out by astrophysical bounds.

4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
18
The categories of this paper are: econ
2
The categories of this paper are: math
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg