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Self-dual variables, positive semi-definite action, and discrete transformations in four-dimensional quantum gravity

Chopin Soo
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Abstract

A positive semi-definite Euclidean action for arbitrary four-topologies can be constructed by adding appropriate Yang-Mills and topological terms to the Samuel-Jacobson-Smolin action of gravity with (anti)self-dual variables. Moreover, on-shell, the (anti)self-dual sector of the new theory corresponds precisely to all Einstein manifolds in four dimensions. The Lorentzian signature action, and its analytic continuations are also considered. A self-contained discussion is given on the effects of discrete transformations C, P and T on the Samuel-Jacobson-Smolin action, and other proposed actions which utilize self- or anti-self-dual variables as fundamental variables in the description of four-dimensional gravity.

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Chopin Soo. 1995-06-30. Self-dual variables, positive semi-definite action, and discrete transformations in four-dimensional quantum gravity. https://doi.org/10.1103/physrevd.52.3484

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