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arXiv · hep-th/9211063

Topological Conformal Gravity in Four Dimensions

Malcolm J. Perry·Edward Teo
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Abstract

In this paper, we present a new formulation of topological conformal gravity in four dimensions. Such a theory was first considered by Witten as a possible gravitational counterpart of topological Yang-Mills theory, but several problems left it incomplete. The key in our approach is to realise a theory which describes deformations of conformally self-dual gravitational instantons. We first identify the appropriate elliptic complex which does precisely this. By applying the Atiyah-Singer index theorem, we calculate the number of independent deformations of a given gravitational instanton which preserve its self-duality. We then quantise topological conformal gravity by BRST gauge-fixing, and discover how the quantum theory is naturally described by the above complex. Indeed, it is a process which closely parallels that of the Yang-Mills theory, and we show how the partition function generates an uncanny gravitational analogue of the first Donaldson invariant.

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Malcolm J. Perry, Edward Teo. 1992-11-14. Topological Conformal Gravity in Four Dimensions. https://doi.org/10.1016/0550-3213(93)90303-7

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