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Geometric Dilaton Coupling and Smooth Charged Wormholes

Wolfgang Graf
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Abstract

A particular type of coupling of the dilaton field to the metric is shown to admit a simple geometric interpretation in terms of a volume element density independent from the metric. For dimension n = 4 two families of either magnetically or electrically charged static spherically symmetric solutions to the Maxwell-Einstein-Dilaton field equations are derived. Whereas the metrics of the "magnetic" spacetimes are smooth, geodesically complete and have the topology of a wormhole, the "electric" metrics behave similarly as the singular and geodesically incomplete classical Reissner-Nordstroem metrics. At the price of losing the simple geometric interpretation, a closely related "alternative" dilaton coupling can nevertheless be defined, admitting as solutions smooth "electric" metrics.

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BibTeXRIS

Wolfgang Graf. 2002-11-03. Geometric Dilaton Coupling and Smooth Charged Wormholes. https://doi.org/10.1103/physrevd.67.024002

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