Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Relativistic spin hydrodynamics with torsion and linear response theory
  for spin relaxation   Using the second law of local thermodynamics and the first-order Palatini
formalism, we formulate relativistic spin hydrodynamics for quantum field
theories with Dirac fermions, such as QED and QCD, in a torsionful curved
background. We work in a regime where spin density, which is assumed to relax
much slower than other non-hydrodynamic modes, is treated as an independent
degree of freedom in an extended hydrodynamic description. Spin hydrodynamics
in our approach contains only three non-hydrodynamic modes corresponding to a
spin vector, whose relaxation time is controlled by a new transport
coefficient: the rotational viscosity. We study linear response theory and
observe an interesting mode mixing phenomenon between the transverse shear and
the spin density modes. We propose several field-theoretical ways to compute
the spin relaxation time and the rotational viscosity, via the Green-Kubo
formula based on retarded correlation functions.

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The categories of this paper are: q-alg
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-lat
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
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The categories of this paper are: mtrl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: eess
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The categories of this paper are: dg-ga
2
The categories of this paper are: math
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The categories of this paper are: cmp-lg
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The categories of this paper are: supr-con
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The categories of this paper are: chao-dyn
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The categories of this paper are: solv-int