Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fundamental Strings and Higher Derivative Corrections to d-Dimensional
  Black Holes   We study aspects of d-dimensional black holes with two electric charges,
corresponding to fundamental strings with generic momentum and winding on an
internal circle. The perturbative alpha' corrections to such black holes and
their gravitational thermodynamics are obtained. The latter are derived using
the Euclidean approach and the Wald formula for the entropy. We find that the
entropy and the charge/mass ratio of black holes increase in alpha' for any
mass and charges, and in all dimensions.

11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
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The categories of this paper are: nucl-ex
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc