Chiral $\Lambda$-$\mathfrak{bms}_4$ symmetry of 3d conformal gravity

Nishant Gupta; Nemani V. Suryanarayana

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arXiv · 2405.20244

Chiral $\Lambda$-$\mathfrak{bms}_4$ symmetry of 3d conformal gravity

Nishant Gupta·Nemani V. Suryanarayana

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Abstract

We propose mixed boundary conditions for 3d conformal gravity consistent with variational principle in its second-order formalism that admit the chiral $\Lambda$-$\mathfrak{bms}_4$ algebra as their asymptotic symmetry algebra. This algebra is one of the four chiral $\mathcal W$-algebra extensions of $\mathfrak{so}(2,3)$ and is a generalisation of the chiral $\mathfrak{bms}_4$ algebra responsible for soft theorems of graviton MHV amplitudes in ${\mathbb R}^{1,3}$ gravity to the case of non-zero negative cosmological constant. The corresponding charges calculated using the modified covariant phase space formalism are shown to be finite and integrable, and realise this non-linear ${\cal W}$-algebra.

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Nishant Gupta, Nemani V. Suryanarayana. 2024-05-30. Chiral $\Lambda$-$\mathfrak{bms}_4$ symmetry of 3d conformal gravity. https://arxiv.org/abs/2405.20244

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