Issue
EPL
Volume 82, Number 6, June 2008
Article Number 65001
Number of page(s) 3
Section Physics of Gases, Plasmas and Electric Discharges
DOI http://dx.doi.org/10.1209/0295-5075/82/65001
Published online 04 June 2008
EPL, 82 (2008) 65001
DOI: 10.1209/0295-5075/82/65001

Ratio of viscosity to entropy density in a strongly coupled one-component plasma

M. H. Thoma and G. E. Morfill

Max-Planck-Institut für extraterrestrische Physik - P.O. Box 1312, 85741 Garching, Germany, EU

thoma@mpe.mpg.de

received 31 March 2008; accepted in final form 2 May 2008; published June 2008
published online 4 June 2008

Abstract
String theoretical arguments led to the hypothesis that the ratio of viscosity to entropy of any physical system has a lower bound. Strongly coupled systems usually have a small viscosity compared to weakly coupled plasmas in which the viscosity is proportional to the mean free path. In the case of a one-component plasma the viscosity as a function of the coupling strength shows a minimum. Here we show that the ratio of viscosity to entropy of a strongly coupled one-component plasma is always above the lower bound predicted by string theory.

PACS
52.27.Gr - Strongly-coupled plasmas.

© EPLA 2008