Abstract

A supersymmetric solution of 5d supergravity may admit an ‘evanescent ergosurface’: a timelike hypersurface such that the canonical Killing vector field is timelike everywhere except on this hypersurface. The hyperkahler ‘base space’ of such a solution is ‘ambipolar’, changing signature from (+ + ++) to (− − −−) across a hypersurface. In this paper, we determine how the hyperkahler structure must degenerate at the hyper-surface in order for the 5d solution to remain smooth. This leads us to a definition of an ambipolar hyperkahler manifold which generalizes the recently-defined notion of a ‘folded’ hyperkahler manifold. We prove that such manifolds can be constructed from ‘initial’ data prescribed on the hypersurface. We present an ‘initial value’ construction of supersymmetric solutions of 5d supergravity, in which such solutions are determined by data prescribed on a timelike hypersurface, both for the generic case and for the case of an evanescent ergosurface.

Highlights

  • The result just summarized concerns configurations of 5d minimal supergravity that admit a supercovariantly constant spinor

  • We present an ‘initial value’ construction of supersymmetric solutions of 5d supergravity, in which such solutions are determined by data prescribed on a timelike hypersurface, both for the generic case and for the case of an evanescent ergosurface

  • If (g, F ) are smooth, admit a supercovariantly constant spinor, and there exists an evanescent ergosurface, the base space must satisfy our definition of an ambipolar hyperkahler manifold

Read more

Summary

Example and definition

We review ‘folded’ hyperkahler manifolds as defined in [1, 2]. While h is undefined at z = 0, the 2-forms X1, X2, X3 are smooth there. Θ is a contact form on S. and θ is a contact form on S From this canonical example, Hitchin [1] extracts a notion of a ‘folded’ hyperkahler manifold. A folded hyperkahler structure consists of a smooth 4-manifold. M, a smooth imbedded hypersurface S ⊂ M (the fold surface), three smooth, closed, 2-forms Xi on M, and a smooth diffeomorphism ι : M → M such that. The 2-forms Xi define a hyperkahler structure on M± with hyperkahler metric h± where h+ has signature (+ + + +) and h− has signature (− − − −); 3.

Construction of folded hyperkahler manifolds
Motivation and definition
Construction of ambipolar hyperkahler manifolds
Evanescent ergosurfaces in 5d supergravity
Supersymmetric configurations of 5d minimal supergravity
Evanescent ergosurfaces
Smoothness of the 5d metric
Smoothness of the Maxwell 2-form F
Sufficient conditions for smoothness
Introduction
Initial data on a regular hypersurface
Ambipolar base space
The f equation
The ω equation
Summary
A The AJS formalism for hyperkahler metrics
B Behavior of f near S

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.