As ambiguidades de escolha de calibre e de parametrização da métrica em gravitação quântica

Abstract

In this thesis we first present a brief historical-motivational for a construction of a theory of quantum gravitation, as well as quick reviews oriented on elements of quantum field theory and Schwinger- Dewitt technique. In possession of these tools, the gauge and parametrization dependence is discussed in quantum gravity in an arbitrary dimension D. Explicit one-loop calculations are performed within the most general parametrization of quantum metric with seven arbitrary parameters. On the other hand, some of the gauge fixing parameters are fixed to make the calculations relatively simple. We confirm the general theorem stating that the on shell local terms in the one-loop effective action are independent of the gauge and parametrization ambiguity.