Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Collective excitations and marginal stability of quantum Ising spin
  glasses   We solve the Sherrington-Kirkpatrick (SK) model in a transverse field \Gamma
deep in its quantum glass phase at zero temperature. We show that the glass
phase is critical everywhere, exhibiting collective excitations with a gapless
Ohmic spectral function. Using an effective potential approach, we interpret
the latter as being due to disordered spin waves which behave as weakly
coupled, underdamped harmonic oscillators. In the limit of small transverse
field the low frequency tail of the spectrum tends to a universal,
\Gamma-independent limit.

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The categories of this paper are: atom-ph
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The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
6
The categories of this paper are: astro-ph