Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exact string backgrounds from WZW models based on non-semi-simple groups   We formulate WZW models based on a centrally extended version of the
Euclidean group in $d$-dimensions. We obtain string backgrounds corresponding
to conformal $\s$-models in $D=d^2$ space-time dimensions with exact central
charge $c=d^2$ and $d(d-1)/2$ null Killing vectors. By identifying the
corresponding conformal field theory we show that the one loop results coincide
with the exact ones up to a shifting of a parameter.

11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics