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arXiv · 1604.03696

BRST Symmetry: Boundary Conditions and Edge States in QED

Nirmalendu Acharyya·A. P. Balachandran·Verónica Errasti Díez·P. N. Bala Subramanian·Sachindeo Vaidya
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Abstract

In manifolds with spatial boundary, BRST formalism can be used to quantize gauge theories. We show that, in a $U(1)$ gauge theory, only a subset of all the boundary conditions allowed by the self-adjointness of the Hamiltonian preserves BRST symmetry. Hence, the theory can be quantized using BRST formalism only when that subset of boundary conditions is considered. We also show that for such boundary conditions, there exist fermionic states which are localized near the boundary.

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Nirmalendu Acharyya, A. P. Balachandran, Verónica Errasti Díez, P. N. Bala Subramanian, Sachindeo Vaidya. 2016-04-19. BRST Symmetry: Boundary Conditions and Edge States in QED. https://doi.org/10.1103/physrevd.94.085026

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