0105088 (Y. Nutku et al.)

A family of heavenly metrics    [PDF]

Y. Nutku, M. B. Sheftel

This is a corrected and essentially extended version of the previous preprint arXiv:gr-qc/0105088 v4 (2002) by Y. Nutku and M. Sheftel containing new results. It is being published now in honor of Y. Nutku's memory. All responsibility for the additions and changes must be attributed to M. Sheftel. We present new anti-self-dual exact solutions of the Einstein field equations with Euclidean and neutral (ultra-hyperbolic) signatures that admit only one rotational Killing vector. Such solutions of the Einstein field equations are determined by non-invariant solutions of Boyer-Finley (BF) equation. For the case of Euclidean signature such a solution of the BF equation was first constructed by Calderbank and Tod. One year later, Martina, Sheftel and Winternitz applied the method of group foliation to the Boyer-Finley equation and reproduced the Calderbank-Tod solution together with new solutions for the neutral signature. We point out that in the case of ultra-hyperbolic signature there exist three inequivalent forms of metric. Only one of these can be obtained by analytic continuation from the Calderbank-Tod solution whereas the other two are new. We obtain new metrics with the Euclidean signature, which asymptotically locally look like a flat space and satisfy regularity conditions, and hence describe gravitational instantons.

View original: http://arxiv.org/abs/0105088