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arXiv · 2510.21636

A truncated photon

Isak Cecil Onsager Rukan·Jan Gulla·Johannes Skaar
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Abstract

An elementary particle such as a photon cannot be cut in two pieces. Still it must be possible to truncate a photon with an optical shutter. The result is neither another photon nor a mix of a photon and a vacuum. Instead it is a superposition and mix of photon numbers up to infinity. This state is rather complicated, but nevertheless locally equivalent to a single photon or vacuum to the left and right, respectively, of a narrow transition region.

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Isak Cecil Onsager Rukan, Jan Gulla, Johannes Skaar. 2025-10-24. A truncated photon. https://doi.org/10.1103/94pm-hp34

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