Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Supermembranes with fewer supersymmetries   The usual supermembrane solution of $D=11$ supergravity interpolates between
$R^{11}$ and $AdS_4 \times round~S^7$, has symmetry $P_3 \times SO(8)$ and
preserves $1/2$ of the spacetime supersymmetries for either orientation of the
round $S^7$. Here we show that more general supermembrane solutions may be
obtained by replacing the round $S^7$ by any seven-dimensional Einstein space
$M^7$. These have symmetry $P_3 \times G$, where $G$ is the isometry group of
$M^7$. For example, $G=SO(5) \times SO(3)$ for the squashed $S^7$. For one
orientation of $M^7$, they preserve $N/16$ spacetime supersymmetries where
$1\leq N \leq 8$ is the number of Killing spinors on $M^7$; for the opposite
orientation they preserve no supersymmetries since then $M^7$ has no Killing
spinors. For example $N=1$ for the left-squashed $S^7$ owing to its $G_2$ Weyl
holonomy, whereas $N=0$ for the right-squashed $S^7$. All these solutions
saturate the same Bogomol'nyi bound between the mass and charge. Similar
replacements of $S^{D-p-2}$ by Einstein spaces $M^{D-p-2}$ yield new super
$p$-brane solutions in other spacetime dimensions $D\leq 11$. In particular,
simultaneous dimensional reduction of the above $D=11$ supermembranes on $S^1$
leads to a new class of $D=10$ elementary string solutions which also have
fewer supersymmetries.

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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: stat
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The categories of this paper are: patt-sol
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-ex
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The categories of this paper are: math
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The categories of this paper are: funct-an
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The categories of this paper are: cmp-lg
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The categories of this paper are: supr-con
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The categories of this paper are: cs
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The categories of this paper are: nlin
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The categories of this paper are: alg-geom
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The categories of this paper are: q-bio
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ex