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arXiv · hep-th/0311127

Spontaneous Breaking of Lorentz Invariance

Alejandro Jenkins
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Abstract

We describe how a stable effective theory in which particles of the same fermion number attract may spontaneously break Lorentz invariance by giving non-zero fermion number density to the vacuum (and therefore dynamically generating a chemical potential term). This mecanism yields a finite vacuum expectation value $<\barψγ^μψ>$ which we consider in the context of proposed models that require such a breaking of Lorentz invariance in order to yield composite degrees of freedom that act approximately like gauge bosons. We also make general remarks about how the background source provided by $<\barψγ^μψ>$ could relate to work on signals of Lorentz violation in electrodynamics.

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Alejandro Jenkins. 2004-05-17. Spontaneous Breaking of Lorentz Invariance. https://doi.org/10.1103/physrevd.69.105007

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