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Berry phase in generalized chiral $QED_2$

Fuad Saradzhev
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Abstract

We consider the generalized chiral $QED_2$ on $S^1$ with a $U(1)$ gauge field coupled with different charges to both chiral components of a fermionic field. Using the adiabatic approximation we calculate the Berry phase and the corresponding ${\rm U}(1)$ connection and curvature for the vacuum and many particle Fock states. We show that the nonvanishing vacuum Berry phase is associated with a projective representation of the local gauge symmetry group and contributes to the effective action of the model.

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Fuad Saradzhev. 1996-09-13. Berry phase in generalized chiral $QED_2$. https://doi.org/10.1088/0305-4470%2F30%2F6%2F040

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