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arXiv · 2308.08342

Gravitational action for a massive Majorana fermion in 2d quantum gravity

Corinne de Lacroix·Harold Erbin·Vincent Lahoche
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Abstract

We compute the gravitational action of a free massive Majorana fermion coupled to two-dimensional gravity on compact Riemann surfaces of arbitrary genus. The structure is similar to the case of the massive scalar. The small-mass expansion of the gravitational yields the Liouville action at zeroth order, and we can identify the Mabuchi action at first order. While the massive Majorana action is a conformal deformation of the massless Majorana CFT, we find an action different from the one given by the David-Distler-Kawai (DDK) ansatz.

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Corinne de Lacroix, Harold Erbin, Vincent Lahoche. 2023-08-16. Gravitational action for a massive Majorana fermion in 2d quantum gravity. https://doi.org/10.1007/jhep01(2024)068

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