Branes at Quantum Criticality

D-Brane Recoil Mislays Information

We discuss the scattering of a light closed-string state off a D brane, taking into account quantum recoil effects on the latter, which are described by a pair of logarithmic operators. The light-particle and D-brane subsystems may each be described by a world-sheet with an external source due to the interaction between them. This perturbs each subsystem away from criticality, which is compensa...

Brany Liouville Inflation

We present a specific model for cosmological inflation driven by the Liouville field in a non-critical supersymmetric string framework, in which the departure from criticality is due to open strings stretched between two moving Type-II 5-branes. We use WMAP and other data on fluctuations in the cosmic microwave background to fix parameters of the model, such as the relative separation and veloc...

Observation of quantum criticality with ultracold atoms in optical lattices.

Quantum criticality emerges when a many-body system is in the proximity of a continuous phase transition that is driven by quantum fluctuations. In the quantum critical regime, exotic, yet universal properties are anticipated; ultracold atoms provide a clean system to test these predictions. We report the observation of quantum criticality with two-dimensional Bose gases in optical lattices. On...

Transmutation of N = 2 fractional D3 branes into twisted sector fluxes

We study the prototype of fractional D3 branes at non-isolated singularities in gauge/gravity duality at the nonperturbative level. We embed the quantum moduli space of N = 2 pure SYM, the gauge theory on fractional D3 branes at the A1 singularity, into that of the cascading quiver gauge theory on regular and fractional D3 branes at the same singularity, for which a gravity dual description exi...

Diffraction line-shapes, Fermi surface nesting, and quantum criticality in antiferromagnetic chromium at high pressure (invited)