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arXiv · hep-th/0005062

Singular Instantons Made Regular

Kelly Kirklin·Neil Turok·Toby Wiseman
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Abstract

The singularity present in cosmological instantons of the Hawking-Turok type is resolved by a conformal transformation, where the conformal factor has a linear zero of codimension one. We show that if the underlying regular manifold is taken to have the topology of $RP^4$, and the conformal factor is taken to be a twisted field so that the zero is enforced, then one obtains a one-parameter family of solutions of the classical field equations, where the minimal action solution has the conformal zero located on a minimal volume noncontractible $RP^3$ submanifold. For instantons with two singularities, the corresponding topology is that of a cylinder $S^3\times [0,1]$ with D=4 analogues of `cross-caps' at each of the endpoints.

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Kelly Kirklin, Neil Turok, Toby Wiseman. 2000-07-14. Singular Instantons Made Regular. https://doi.org/10.1103/physrevd.63.083509

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