出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：On a lattice, we construct an overlap Dirac operator which describes the propagation of a Dirac
fermion in external gravity. The local Lorentz symmetry is manifestly realized as a lattice gauge
symmetry, while the general coordinate invariance is expected to be restored only in the continuum
limit. The lattice index density in the presence of a gravitational field is calculated.
