Conformal wave expansions for flat space amplitudes

Liu, Chang; Lowe, David A.

doi:10.1007/jhep07(2021)102

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Conformal wave expansions for flat space amplitudes

Liu, Chang·Lowe, David A.

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Abstract

The extended BMS algebra contains a conformal subgroup that acts on the celestial sphere as SO(1, 3). It is of interest to perform mode expansions of free fields in Minkowski spacetime that realize this symmetry in a simple way. In the present work we perform such a mode expansion for massive scalar fields using the unitary principal series representations of SO(1, 3) with a view to developing a holographic approach to gravity in asymptotically flat spacetime. These mode expansions are also of use in studying holography in three-dimensional de Sitter spacetime.

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Liu, Chang, Lowe, David A.. 2021-07-15. Conformal wave expansions for flat space amplitudes. https://doi.org/10.1007/jhep07(2021)102

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