1993/09/30 by Fay Dowker, Jerome P. Gauntlett, David Kastor +2 · 4 citations
Mathematics · Physics and Astronomy · #Black Holes and Theoretical Physics #Combinatorics #Cosmology and Gravitation Theories #Dilaton #Gravitational singularity #Instanton #Mathematical physics #Mathematics #Physics #Quantum mechanics #Relativity and Gravitational Theory #Spacetime #Theoretical physics #Topology (electrical circuits) #gr-qc #hep-th
paper · pdf · doi:10.1103/physrevd.49.2909
published as Phys.Rev.D49:2909-2917,1994 · 22 pages, EFI-93-51, FERMILAB-Pub-93/272-A, UMHEP-393. (Asymptotics of Ernst solutions clarified, typos repaired)
arxiv created 1993/11/22 · openalex publication_date 1994/03/15 · arxiv updated 2014/11/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We consider dilaton gravity theories in four spacetime dimensions parametrized by a constant a, which controls the dilaton coupling, and construct new exact solutions. We first generalize the C metric of Einstein-Maxwell theory (a=0) to solutions corresponding to oppositely charged dilaton black holes undergoing uniform acceleration for general a. We next develop a solution-generating technique which allows us to ``embed'' the dilaton C metrics in magnetic dilaton Melvin backgrounds, thus generalizing the Ernst metric of Einstein-Maxwell theory. By adjusting the parameters appropriately, it is possible to eliminate the nodal singularities of the dilaton C metrics. For a1 (but not for a\ensuremath≥1), it is possible to further restrict the parameters so that the dilaton Ernst solutions have a smooth Euclidean section with topology S2\ifmmode×\else\texttimes\fiS2-pt, corresponding to instantons describing the pair production of dilaton black holes in a magnetic field. A different restriction on the parameters leads to smooth instantons for all values of a with topology S2\ifmmode×\else\texttimes\fiopenR2.