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arXiv · 1512.01352

Emergent geometries and nonlinear-wave dynamics in photon fluids

Francesco Marino·Calum Maitland·David Vocke·Antonello Ortolan·Daniele Faccio
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Abstract

Nonlinear waves in defocusing media are investigated in the framework of the hydrodynamic description of light as a photon fluid. The observations are interpreted in terms of an emergent curved spacetime generated by the waves themselves, which fully determines their dynamics. The spacetime geometry emerges naturally as a result of the nonlinear interaction between the waves and the self-induced background flow. In particular, as observed in real fluids, different points of the wave profile propagate at different velocities leading to the self-steepening of the wave front and to the formation of a shock. This phenomenon can be associated to a curvature singularity of the emergent metric. Our analysis offers an alternative insight into the problem of shock formation and provides a demonstration of an analogue gravity model that goes beyond the kinematic level.

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Francesco Marino, Calum Maitland, David Vocke, Antonello Ortolan, Daniele Faccio. 2015-12-04. Emergent geometries and nonlinear-wave dynamics in photon fluids. https://arxiv.org/abs/1512.01352

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