Dispersive and dissipative effects in quantum field theory in curved space-time to model condensed matter systems

TL;DR

This paper investigates how dispersion and dissipation influence quantum field phenomena like Hawking radiation and pair production, using analogies with condensed matter systems to enable laboratory testing of these effects.

Contribution

It provides explicit analysis of dispersion and dissipation effects on quantum phenomena in curved spacetime, applying exact results from de Sitter space to black hole analogues and condensed matter systems.

Findings

Dispersion and dissipation modify Hawking radiation and pair production.

Entanglement properties are affected by dissipation and dispersion.

Analogue condensed matter systems can simulate quantum field effects in curved spacetime.

Abstract

The two main predictions of quantum field theory in curved space-time, namely Hawking radiation and cosmological pair production, have not been directly tested and involve ultra high energy configurations. As a consequence, they should be considered with caution. Using the analogy with condensed matter systems, their analogue versions could be tested in the lab. Moreover, the high energy behavior of these systems is known and involves dispersion and dissipation, which regulate the theory at short distances. When considering experiments which aim to test the above predictions, there will also be a competition between the stimulated emission from thermal noise and the spontaneous emission out of vacuum. In order to measure these effects, one should thus compute the consequences of UV dispersion and dissipation, and identify observables able to establish that the spontaneous emission took place. In this thesis, we first analyze the effects of dispersion and dissipation on both Hawking radiation and pair particle production. To get explicit results, we work in the context of de Sitter space. Using the extended symmetries of the theory in such a background, exact results are obtained. These are then transposed to the context of black holes using the correspondence between de Sitter space and the black hole near horizon region. To introduce dissipation, we consider an exactly solvable model producing any decay rate. We also study the quantum entanglement of the particles so produced. In a second part, we consider explicit condensed matter systems, namely Bose Einstein condensates and exciton-polariton systems. We analyze the effects of dissipation on entanglement produced by the dynamical Casimir effect. As a final step, we study the entanglement of Hawking radiation in the presence of dispersion for a generic analogue system.