Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the structure of pseudo-Riemannian symmetric spaces   Following our approach to metric Lie algebras developed in math.DG/0312243 we
propose a way of understanding pseudo-Riemannian symmetric spaces which are not
semi-simple. We introduce cohomology sets (called quadratic cohomology)
associated with orthogonal modules of Lie algebras with involution. Then we
construct a functorial assignment which sends a pseudo-Riemannian symmetric
space M to a triple consisting of
  (i) a Lie algebra with involution (of dimension much smaller than the
dimension of the transvection group of M),
  (ii) a semi-simple orthogonal module of the Lie algebra with involution, and
  (iii) a quadratic cohomology class of this module.
  That leads to a classification scheme of indecomposable non-simple
pseudo-Riemannian symmetric spaces. In addition, we obtain a full
classification of symmetric spaces of index 2 (thereby completing and
correcting in part earlier classification results due to Cahen/Parker and
Neukirchner math.DG/0301326).

5
The categories of this paper are: gr-qc
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org