Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Phase Transition in the Sub-Ohmic Spin-Boson Model: Extended
  Coherent-state Approach   We propose a general extended coherent state approach to the qubit (or
fermion) and multi-mode boson coupling systems. The application to the
spin-boson model with the discretization of a bosonic bath with arbitrary
continuous spectral density is described in detail, and very accurate solutions
can be obtained. The quantum phase transition in the nontrivial sub-Ohmic case
can be located by the fidelity and the order-parameter critical exponents for
the bath exponents $s<1/2$ can be correctly given by the fidelity
susceptibility, demonstrating the strength of the approach.

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The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: eess
28
The categories of this paper are: alg-geom
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
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The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci