First order, 2D, Einstein gravities

Abstract

This paper is dedicated to the memory of M. Markov, whose commitment to Quantum Gravity through the Seminars he organized made possible contacts across borders when they were most needed. The Palatini variational method breaks down in 2D: First order forms of the Einstein action do not fix the affinity completely, as they possess an additional, Weyl, invariance absent in the second order versions.

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