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arXiv · 1810.11361

Temporally, Spatially or Light-like Modulated Vacua in Lorentz Invariant Theories

Sven Bjarke Gudnason·Muneto Nitta·Shin Sasaki·Ryo Yokokura
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Abstract

We study the vacuum structure of a class of Lorentz invariant field theories where the vacuum expectation values are not constant but are (phase) modulated. The vacua are classified into spatial, temporal, and light-like modulation types according to the patterns of spontaneous breaking of translational symmetry. The conditions for having temporal or light-like modulated vacua imply severe constraints on the models. We utilize the notion of generalized Nambu-Goldstone modes which appear in the modulated vacua. Finally, we examine fluctuation modes around these vacua and discuss their dynamics and the absence of ghosts.

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Sven Bjarke Gudnason, Muneto Nitta, Shin Sasaki, Ryo Yokokura. 2018-10-26. Temporally, Spatially or Light-like Modulated Vacua in Lorentz Invariant Theories. https://doi.org/10.1103/physrevd.99.045011

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