Who has seen a free photon?

Izumi Ojima; Hayato Saigo

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arXiv · 1101.5782

Who has seen a free photon?

Izumi Ojima·Hayato Saigo

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Abstract

While the notion of the position of photons is indispensable in the quantum optical situations, it has been known in mathematical physics that any position operator cannot be defined for a massless free particle with a non-zero finite spin. This dilemma is resolved by introducing the "effective mass" of a photon due to the interaction with matter. The validity of this interpretation is confirmed in reference to the picture of "polariton", a basic notion in optical and solid physics. In this connection, we discuss the long-standing controversy between Minkowski's and Abraham's definitions of the momenta of a photon in media from the general viewpoint adopted in the appendix.

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Izumi Ojima, Hayato Saigo. 2011-01-30. Who has seen a free photon?. https://arxiv.org/abs/1101.5782

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