On deformations and extensions of Diff(S.sup.2./sup.)

0552333 - FZÚ 2022 RIV US eng J - Článek v odborném periodiku
Rojo, M.E. - Procházka, Tomáš - Sachs, I.
On deformations and extensions of Diff(S²).
Journal of High Energy Physics. Roč. 2021, č. 10 (2021), č. článku 133. ISSN 1029-8479. E-ISSN 1029-8479
Grant CEP: GA ČR(CZ) GX20-25775X
Institucionální podpora: RVO:68378271
Klíčová slova: representations * algebras * space-time symmetries * cassical theories of gravity * conformal and W symmetry * gauge-gravity correspondence
Obor OECD: Particles and field physics
Impakt faktor: 6.376, rok: 2021
Způsob publikování: Open access

We investigate the algebra of vector fields on the sphere. First, we find that linear deformations of this algebra are obstructed under reasonable conditions. In particular, we show that hs[λ], the one-parameter deformation of the algebra of area-preserving vector fields, does not extend to the entire algebra. Next, we study some non-central extensions through the embedding of vect mathfrak{vect} vect(S2^{2}2) into vect mathfrak{vect} vect(ℂ∗^{*}∗). For the latter, we discuss a three parameter family of non-central extensions which contains the symmetry algebra of asymptotically flat and asymptotically Friedmann spacetimes at future null infinity, admitting a simple free field realization.
Trvalý link: http://hdl.handle.net/11104/0327474