Bulk viscosity of N=2∗N=2∗ plasma

We use gauge theory/string theory correspondence to study bulk viscosity of strongly coupled mass deformed SU(Nc)SU(Nc)N=4N=4 supersymmetric Yang–Mills plasma, also known as N=2∗N=2∗ gauge theory. For a wide range of masses we confirm the bulk viscosity bound proposed in [A. Buchel, Phys. Lett. B 663 (2008) 286, arXiv:0708.3459 [hep-th]]. For certain choice of masses, the theory undergoes a phase transition with divergent specific heat cV∼|1−Tc/T|−1/2cV∼|1−Tc/T|−1/2. We show that, although bulk viscosity rapidly grows as T→TcT→Tc, it remains finite in the vicinity of the critical point.