# Notes on the BMS group in three dimensions: II. Coadjoint representation

@article{Barnich2015NotesOT, title={Notes on the BMS group in three dimensions: II. Coadjoint representation}, author={Glenn Barnich and Blagoje Oblak}, journal={Journal of High Energy Physics}, year={2015}, volume={2015}, pages={1-18} }

A bstractThe coadjoint representation of the BMS3 group, which governs the covariant phase space of three-dimensional asymptotically flat gravity, is investigated. In particular, we classify coadjoint BMS3 orbits and show that intrinsic angular momentum is free of supertranslation ambiguities. Finally, we discuss the link with induced representations upon geometric quantization.

## 96 Citations

### Notes on the BMS group in three dimensions: I. Induced representations

- Mathematics
- 2014

A bstractThe Bondi-Metzner-Sachs group in three dimensions is the symmetry group of asymptotically flat three-dimensional spacetimes. It is the semi-direct product of the diffeomorphism group of the…

### Coadjoint representation of the BMS group on celestial Riemann surfaces

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Abstract
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### Characters of the BMS Group in Three Dimensions

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Using the Frobenius formula, we evaluate characters associated with certain induced representations of the centrally extended BMS3 group. This computation involves a functional integral over a…

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- 2016

We build unitary representations of the BMS algebra and its higher-spin extensions in three dimensions, using induced representations as a guide. Our prescription naturally emerges from an…

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The solution space of three-dimensional asymptotically anti-de Sitter or flat Einstein gravity is given by the coadjoint representation of two copies of the Virasoro group in the former and the…

### Coadjoint Orbits of the Poincaré Group for Discrete-Spin Particles in Any Dimension

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Considering the Poincaré group ISO(d−1,1) in any dimension d>3, we characterise the coadjoint orbits that are associated with massive and massless particles of discrete spin. We also comment on how…

### Holographic positive energy theorems in three-dimensional gravity

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- 2014

The covariant phase space of three-dimensional asymptotically flat and anti-de Sitter gravity is controlled by well-understood coadjoint orbits of the Virasoro group. Detailed knowledge on the…

### Asymptotically flat spacetimes with BMS3 symmetry

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We construct the phase space of 3-dimensional asymptotically flat spacetimes that forms the bulk metric representation of the BMS group consisting of both supertranslations and superrotations. The…

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The Bondi-Metzner-Sachs-van der Burg (BMS) group is the asymptotic symmetry group of radiating asymptotically flat spacetimes. It has recently received renewed interest in the context of the flat…

### Coadjoint Orbits and Geometric Quantization

- Physics, Biology
- 2017

This chapter is to describe the opposite phenomenon: starting from a coadjoint orbit of a group G, the orbit will obtain a representation by quantizing the orbit, which will further explain why orbits of momenta classify representations of semi-direct products.

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A bstractThe Bondi-Metzner-Sachs group in three dimensions is the symmetry group of asymptotically flat three-dimensional spacetimes. It is the semi-direct product of the diffeomorphism group of the…

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