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arXiv · hep-th/9607206

Quantum Topological Invariants, Gravitational Instantons and the Topological Embedding

Damiano Anselmi
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Abstract

Certain topological invariants of the moduli space of gravitational instantons are defined and studied. Several amplitudes of two and four dimensional topological gravity are computed. A notion of puncture in four dimensions, that is particularly meaningful in the class of Weyl instantons, is introduced. The topological embedding, a theoretical framework for constructing physical amplitudes that are well-defined order by order in perturbation theory around instantons, is explicitly applied to the computation of the correlation functions of Dirac fermions in a punctured gravitational background, as well as to the most general QED and QCD amplitude. Various alternatives are worked out, discussed and compared. The quantum background affects the propagation by generating a certain effective ``quantum'' metric. The topological embedding could represent a new chapter of quantum field theory.

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Damiano Anselmi. 1996-07-27. Quantum Topological Invariants, Gravitational Instantons and the Topological Embedding. https://doi.org/10.1088/0264-9381%2F14%2F8%2F006

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