AUTHOR=Brevik Iver H.

TITLE=Viscosity-induced crossing of the phantom divide in the dark cosmic fluid

JOURNAL=Frontiers in Physics

VOLUME=1

YEAR=2013

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2013.00027

DOI=10.3389/fphy.2013.00027

ISSN=2296-424X

ABSTRACT=<p>Choosing various natural forms for the equation-of-state parameter <italic>w</italic> and the bulk viscosity ζ, we discuss how it is possible for a dark energy fluid to slide from the quintessence region across the divide <italic>w</italic> = −1 into the phantom region, and thus into a Big Rip future singularity. Different analytic forms for ζ, as powers of the scalar expansion, are suggested and compared with experiments.</p>