How a-Type Anomalies Can Depend on Marginal Couplings.

Even dimensional defects and boundaries in conformal field theory support type a anomalies on their world volume. We show that the one-point functions of marginal operators, in the presence of defects and boundaries, are anomalous, and that the Wess-Zumino consistency condition relates them to the derivative of the a anomaly with respect to the marginal coupling. We also argue that the constant term F for odd dimensional surfaces can depend on marginal parameters.

Universal thermal corrections to single interval entanglement entropy for two dimensional conformal field theories.

We consider single interval Rényi and entanglement entropies for a two dimensional conformal field theory on a circle at nonzero temperature. Assuming that the finite size of the system introduces a unique ground state with a nonzero mass gap, we calculate the leading corrections to the Rényi and entanglement entropy in a low temperature expansion. These corrections have a universal form for any two dimensional conformal field theory that depends only on the size of the mass gap and its degeneracy. We analyze the limits where the size of the interval becomes small and where it becomes close to the size of the spatial circle.

Superconductors from superstrings.

We establish that in a large class of strongly coupled (3+1)-dimensional N=1 quiver conformal field theories with gravity duals, adding a chemical potential for the R charge leads to the existence of superfluid states in which a chiral primary operator of the schematic form O=lambdalambda+W condenses. Here lambda is a gluino and W is the superpotential. Our argument is based on the construction of a consistent truncation of type IIB supergravity that includes a U(1) gauge field and a complex scalar.

Building a holographic superconductor.

We show that a simple gravitational theory can provide a holographically dual description of a superconductor. There is a critical temperature, below which a charged condensate forms via a second order phase transition and the (dc) conductivity becomes infinite. The frequency dependent conductivity develops a gap determined by the condensate. We find evidence that the condensate consists of pairs of quasiparticles.

Holographic prediction for the deconfinement temperature.

We argue that deconfinement in anti-de Sitter space models of quantum chromodynamics (AdS/QCD models) occurs via a first order Hawking-Page type phase transition between low temperature thermal AdS and a high temperature black hole. Such a result is consistent with the expected temperature independence, to leading order in 1/Nc, of the meson spectrum and spatial Wilson loops below the deconfinement temperature. As a by-product, we obtain model dependent deconfinement temperatures Tc in the hard- and soft-wall models of AdS/QCD. Our result for Tc in the soft-wall model is close to a recent lattice prediction.