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arXiv · hep-lat/9403020

Negative-Energy Spinors and the Fock Space of Lattice Fermions at Finite Chemical Potential

E. Mendel·L. Polley
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Abstract

Recently it was suggested that the problem of species doubling with Kogut-Susskind lattice fermions entails, at finite chemical potential, a confusion of particles with antiparticles. What happens instead is that the familiar correspondence of positive-energy spinors to particles, and of negative-energy spinors to antiparticles, ceases to hold for the Kogut-Susskind time derivative. To show this we highlight the role of the spinorial ``energy'' in the Osterwalder-Schrader reconstruction of the Fock space of non-interacting lattice fermions at zero temperature and nonzero chemical potential. We consider Kogut-Susskind fermions and, for comparison, fermions with an asymmetric one-step time derivative.

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E. Mendel, L. Polley. 1994-06-10. Negative-Energy Spinors and the Fock Space of Lattice Fermions at Finite Chemical Potential. https://doi.org/10.1007/bf01571313

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