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arXiv · 1808.07453

Analog of cosmological particle creation in electromagnetic waveguides

Sascha Lang·Ralf Schützhold
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Abstract

We consider an electromagnetic waveguide with a time-dependent propagation speed $v(t)$ as an analog for cosmological particle creation. In contrast to most previous studies which focus on the number of particles produced, we calculate the corresponding two-point correlation function. For a small step-like variation $δv(t)$, this correlator displays characteristic signatures of particle pair creation. As another potential advantage, this observable is of first order in the perturbation $δv(t)$, whereas the particle number is second order in $δv(t)$ and thus stronger suppressed for small $δv(t)$.

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Sascha Lang, Ralf Schützhold. 2019-05-27. Analog of cosmological particle creation in electromagnetic waveguides. https://doi.org/10.1103/physrevd.100.065003

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