Found 3 result(s)
Journal Club Jorge Russo (University of Barcelona)
room Zoom, instructions in abstract
We investigate the different large N phases of a deformed Gross-Witten-Wadia U(N) matrix model. The deformation, which leads to a solvable model, corresponds to the addition of characteristic polynomial insertions and mimicks the one-loop determinant of fermion matter. In one version of the model, the GWW phase transition is smoothed out and it becomes a crossover. In another version, the phase transition occurs along a critical line in the two-dimensional parameter space spanned by the 't~Hooft coupling $\lambda $ and the Veneziano parameter $\tau $. A calculation of the $\beta $ function shows the existence of an IR stable fixed point. ---- Part of London Integrability Journal Club. If you are a new participant, please register filling the form at integrability-london.weebly.com. The link will be emailed.
Triangular Seminar Jorge Russo (Barcelona)
room UG1 in Physics Building
Gauged supergravities arise from consistent truncations of string theory and provide a solid framework for condensed matter applications, in a context where the dual field theory is well understood. In this talk we shall discuss different models, including p-wave superconductivity by condensation of a two-form potential.
Regular Seminar Jorge Russo (University of Barcelona)
room Huxley 503
The exact string coupling dependence of higher derivative terms in the type IIA and type IIB effective action is highly constrained by a combination of duality symmetries and by results from perturbative string theory. For example, we show that terms of the form D to the 2k times R to the 4th in type IIA theory should receive no perturbative contributions beyond genus k (k greater than 0). We also propose that the exact modular functions of general type IIB higher derivative terms are determined by a Poisson equation on the fundamental domain of the moduli space.