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arXiv · 2107.00478

Hunting dark energy with pressure-dependent photon-photon scattering

Taishi Katsuragawa·Shinya Matsuzaki·Kensuke Homma
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Abstract

Toward understanding of dark energy, we propose a novel method to directly produce a chameleon particle and force its decay under controlled gas pressure in a laboratory-based experiment. {\it Chameleon gravity}, characterized by its varying mass depending on its environment, could be a source of dark energy, which is predicted in modified gravity. A remarkable finding is a correspondence between the varying mass and a characteristic pressure dependence of a stimulated photon-photon scattering rate in a dilute gas surrounding a focused photon-beam spot. By observing a steep pressure dependence in the scattering rate, we can directly extract the characteristic feature of the chameleon mechanism. As a benchmark model of modified gravity consistent with the present cosmological observations, a reduced $F(R)$ gravity is introduced in the laboratory scale. We then demonstrate that the proposed method indeed enables a wide-ranging parameter scan of such a chameleon model with the varying mass around $(0.1-1)~[\mu \mathrm{eV}]$ by controlling pressure values.

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Taishi Katsuragawa, Shinya Matsuzaki, Kensuke Homma. 2021-07-01. Hunting dark energy with pressure-dependent photon-photon scattering. https://doi.org/10.1103/physrevd.106.044011

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