The transport properties of certain strongly coupled thermal gauge theories can be determined from their effective description in terms of gravity or superstring theory duals. Here we provide a short summary of the results for the shear and bulk viscosity, charge diffusion constant, and the speed of sound in supersymmetric strongly interacting plasmas. We also outline a general algorithm for co...

A bstract We construct higher spin quasinormal modes algebraically in D -dimensional de Sitter spacetime using the ambient space formalism. The fall into two nonunitary lowest-weight representations of $$ \mathfrak{so} so (1 , ). From a local QFT point view, massless fields are produced by gauge-invariant bou...

We extensively study the exact solutions of the massless Dirac equation in 3D de Sitter spacetime that we published recently. Using the Newman-Penrose formalism, we find exact solutions of the equations of motion for the massless classical fields of spin s = 12 , 1, 2 and to the massive Dirac equation in 4D de Sitter metric. Employing these solutions, we analyze the absorption by the cosmologic...

The phenomenon of coherent wave trapping and restoration is demonstrated experimentally in a magnonic crystal. Unlike the conventional scheme used in photonics, the trapping occurs not due to the deceleration of the incident wave when it enters the periodic structure but due to excitation of the quasinormal modes of the artificial crystal. This excitation occurs at the group velocity minima of ...