Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The $\alpha'$ Expansion On A Compact Manifold Of Exceptional Holonomy   In the approximation corresponding to the classical Einstein equations, which
is valid at large radius, string theory compactification on a compact manifold
$M$ of $G_2$ or $\mathrm{Spin}(7)$ holonomy gives a supersymmetric vacuum in
three or two dimensions. Do $\alpha'$ corrections to the Einstein equations
disturb this statement? Explicitly analyzing the leading correction, we show
that the metric of $M$ can be adjusted to maintain supersymmetry. Beyond
leading order, a general argument based on low energy effective field theory in
spacetime implies that this is true exactly (not just to all finite orders in
$\alpha'$). A more elaborate field theory argument that includes the massive
Kaluza-Klein modes matches the structure found in explicit calculations. In
M-theory compactification on a manifold $M$ of $G_2$ or Spin(7) holonomy,
similar results hold to all orders in the inverse radius of $M$ -- but not
exactly. The classical moduli space of $G_2$ metrics on a manifold $M$ is known
to be locally a Lagrangian submanifold of $H^3(M,{\mathbf R})\oplus
H^4(M,\mathbf{R})$. We show that this remains valid to all orders in the
$\alpha'$ or inverse radius expansion.

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The categories of this paper are: hep-lat
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The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
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The categories of this paper are: dg-ga
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The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: astro-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: q-bio
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The categories of this paper are: gr-qc
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The categories of this paper are: acc-phys
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The categories of this paper are: adap-org