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arXiv · 1902.02209

Using a black hole to weigh light: can the Event Horizon Telescope yield new information about the photon rest mass?

Robert P. Cameron
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Abstract

We point out that data collected by the Event Horizon Telescope or a similar project might yield new information about the photon rest mass $m_\gamma$, in the form of evidence that $m_\gamma\ne 0$ together with a lower bound on $m_\gamma$ or a new upper bound on $m_\gamma$. Using Sgr A*, there is scope to improve on the best upper bound obtained via laboratory tests of Coulomb's law by up to nineteen orders of magnitude.

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Robert P. Cameron. 2019-02-06. Using a black hole to weigh light: can the Event Horizon Telescope yield new information about the photon rest mass?. https://arxiv.org/abs/1902.02209

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