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arXiv · hep-th/0109120

Origin of Light

Xiao-Gang Wen
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Abstract

The existence of light (a massless U(1) gauge boson) is one of unresolved mysteries in nature. In this paper, we would like to propose that light is originated from certain quantum orders in our vacuum. We will construct quantum models on lattice to demonstrate that some quantum orders can give rise to light without breaking any symmetries and without any fine tuning. Through our models, we show that the existence of light can simply be a phenomenon of quantum coherence in a system with many degrees of freedom. Massless gauge fluctuations appears commonly and naturally in strongly correlated systems.

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Xiao-Gang Wen. 2001-09-20. Origin of Light. https://doi.org/10.1103/physrevlett.88.011602

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