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arXiv · 1010.3121

Shear Viscosity in Weakly Coupled N-Component Scalar Field Theories

Jiunn-Wei Chen·Mei Huang·Chang-Tse Hsieh·Han-Hsin Lin
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Abstract

The rich phenomena of the shear viscosity (eta) to entropy density (s) ratio, eta/s, in weakly coupled N-component scalar field theories are studied. eta/s can have a "double dip" behavior due to resonances and the phase transition. If an explicit goldstone mass term is added, then eta/s can either decrease monotonically in temperature or, as seen in many other systems, reach a minimum at the phase transition. We also show how to go beyond the original variational approach to make the Boltzmann equation computation of eta systematic.

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Jiunn-Wei Chen, Mei Huang, Chang-Tse Hsieh, Han-Hsin Lin. 2010-11-18. Shear Viscosity in Weakly Coupled N-Component Scalar Field Theories. https://doi.org/10.1103/physrevd.83.115006

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