GOVER, A. Rod, Katharina NEUSSER and Travis WILLSE. Compactifications of indefinite 3-Sasaki structures and their quaternionic Kähler quotients. Annali di Matematica Pura ed Applicata. Springer, 2024, vol. 203, April 2024, p. 875-902. ISSN 0373-3114. Available from: https://dx.doi.org/10.1007/s10231-023-01385-0.
Other formats:   BibTeX LaTeX RIS
Basic information
Original name Compactifications of indefinite 3-Sasaki structures and their quaternionic Kähler quotients
Authors GOVER, A. Rod, Katharina NEUSSER (40 Austria, guarantor, belonging to the institution) and Travis WILLSE.
Edition Annali di Matematica Pura ed Applicata, Springer, 2024, 0373-3114.
Other information
Original language English
Type of outcome Article in a journal
Field of Study 10101 Pure mathematics
Country of publisher Germany
Confidentiality degree is not subject to a state or trade secret
WWW URL
Impact factor Impact factor: 1.000 in 2022
Organization unit Faculty of Science
Doi http://dx.doi.org/10.1007/s10231-023-01385-0
UT WoS 001091151700001
Keywords in English Projective differential geometry; Einstein manifolds; Sasaki manifolds; Hyper-Kähler and quaternionic Kähler geometry; Holonomy; Geometric compactifications
Tags rivok
Tags International impact, Reviewed
Changed by Changed by: Mgr. Marie Šípková, DiS., učo 437722. Changed: 12/3/2024 14:34.
Abstract
We show that 3-Sasaki structures admit a natural description in terms of projective differential geometry. First we establish that a 3-Sasaki structure may be understood as a projective structure whose tractor connection admits a holonomy reduction, satisfying a particular non-vanishing condition, to the (possibly indefinite) unitary quaternionic group Sp(p, q). Moreover, we show that, if a holonomy reduction to Sp(p, q) of the tractor connection of a projective structure does not satisfy this condition, then it decomposes the underlying manifold into a disjoint union of strata including open manifolds with (indefinite) 3-Sasaki structures and a closed separating hypersurface at infinity with respect to the 3-Sasaki metrics. It is shown that the latter hypersurface inherits a Biquard–Fefferman conformal structure, which thus (locally) fibers over a quaternionic contact structure, and which in turn compactifies the natural quaternionic Kähler quotients of the 3-Sasaki structures on the open manifolds. As an application, we describe the projective compactification of (suitably) complete, non-compact (indefinite) 3-Sasaki manifolds and recover Biquard’s notion of asymptotically hyperbolic quaternionic Kähler metrics.
Links
GA19-06357S, research and development projectName: Geometrické struktury, diferenciální operátory a symetrie (Acronym: GSDOS)
Investor: Czech Science Foundation
PrintDisplayed: 21/5/2024 19:23