Table of Contents Author Guidelines Submit a Manuscript
Advances in High Energy Physics
Volume 2014, Article ID 670598, 17 pages
http://dx.doi.org/10.1155/2014/670598
Research Article

Langevin Diffusion in Holographic Backgrounds with Hyperscaling Violation

Department of Physics, Sciences Faculty, Mazandaran University, P.O. Box 47415-416, Babolsar, Iran

Received 18 May 2014; Accepted 9 September 2014; Published 20 October 2014

Academic Editor: Reinhard Schlickeiser

Copyright © 2014 J. Sadeghi and F. Pourasadollah. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The publication of this article was funded by SCOAP3.

Abstract

We consider a relativistic heavy quark which moves in the quark-gluon plasmas. By using the holographic methods, we analyze the Langevin diffusion process of this relativistic heavy quark. This heavy quark is described by a trailing string attached to a flavor brane and moving at constant velocity. The fluctuations of this string are related to the thermal correlators and the correlation functions are precisely the kinds of objects that we compute in the gravity dual picture. We obtain the action of the trailing string in hyperscaling violation backgrounds and we then find the equations of motion. These equations lead us to constructing the Langevin correlator which helps us to obtain the Langevin constants. Using the Langevin correlators we derive the spectral densities and simple analytic expressions in the small- and large-frequency limits. We examine our works for planar and -charged black holes with hyperscaling violation and find new constraints on in the presence of velocity .