Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Response of Holographic QCD to Electric and Magnetic Fields   We study the response of the Sakai-Sugimoto holographic model of large N_c
QCD at nonzero temperature to external electric and magnetic fields. In the
electric case we find a first-order insulator-conductor transition in both the
confining and deconfining phases of the model. In the deconfining phase the
conductor is described by the parallel 8-brane-anti-8-brane embedding with a
current of quarks and anti-quarks. We compute the conductivity and show that it
agrees precisely with a computation using the Kubo formula. In the confining
phase we propose a new kind of 8-brane embedding, corresponding to a baryonic
conductor. In the magnetic field case we show that the critical temperature for
chiral-symmetry restoration in the deconfined phase increases with the field
and approaches a finite value in the limit of an infinite magnetic field. We
also illustrate the nonlinear behavior of the electric and magnetic
susceptibilities in the different phases.

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The categories of this paper are: math
15
The categories of this paper are: nucl-ex
29
The categories of this paper are: funct-an
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
26
The categories of this paper are: bayes-an
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
14
The categories of this paper are: math-ph
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The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys