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Quantum phase transition for the BEC--BCS crossover in condensed matter physics and CPT violation in elementary particle physics

F. R. Klinkhamer·G. E. Volovik
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Abstract

We discuss the quantum phase transition that separates a vacuum state with fully-gapped fermion spectrum from a vacuum state with topologically-protected Fermi points (gap nodes). In the context of condensed-matter physics, such a quantum phase transition with Fermi point splitting may occur for a system of ultracold fermionic atoms in the region of the BEC-BCS crossover, provided Cooper pairing occurs in the non-s-wave channel. For elementary particle physics, the splitting of Fermi points may lead to CPT violation, neutrino oscillations, and other phenomena.

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F. R. Klinkhamer, G. E. Volovik. 2004-11-04. Quantum phase transition for the BEC--BCS crossover in condensed matter physics and CPT violation in elementary particle physics. https://doi.org/10.1134/1.1825119

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