Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Supersymmetry of AdS and flat backgrounds in M-theory   We give a systematic description of all warped $AdS_n$ and
${\mathbb{R}}^{n-1,1}$ backgrounds of M-theory and identify the a priori number
of supersymmetries that these backgrounds preserve. In particular, we show that
$AdS_n$ backgrounds preserve $N= 2^{[{n\over2}]} k$ for $n\leq4$ and $N=
2^{[{n\over2}]+1} k$ for $4<n\leq 7$ supersymmetries while
${\mathbb{R}}^{n-1,1}$ backgrounds preserve $N= 2^{[{n\over2}]} k$ for $n\leq4$
and $N= 2^{[{n+1\over2}]} k$ for $4<n\leq7$, supersymmetries. Furthermore for
$AdS_n$ backgrounds that satisfy the requirements for the maximum principle to
hold, we show that the Killing spinors can be identified with the zero modes of
Dirac-like operators on $M^{11-n}$ coupled to fluxes thus establishing a new
class of Lichnerowicz type theorems. We also demonstrate that the Killing
spinors of generic warped $AdS_n$ backgrounds do not factorize into products of
Killing spinors on $AdS_n$ and Killing spinors on the transverse space.

28
The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
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
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg