For less than BH_h, deep in gravitational potential well, with very extreme curvature, might one have a future light cone tipping over sufficiently to become spacelike and then wrap around to join up (glued) to past light cone? This is like a closed timelike curve, which can not be shrunk to a point. "[URL [Broken] So it would have a(adsbygoogle = window.adsbygoogle || []).push({}); toruslike topology; very different from our future light cone, which is finite and bounded in timelike sense, and hence not closed. So also topologically, any CTC would seem quite different from topology of C_R for greater than and less than BH_h.

also: 'The Kerr vacuum is unobjectionable and realistic (for black hole models) in the exterior regions, and unobjectionable but perhaps unrealistic (for black hole models) in the "shallow interior" regions, but as several commentators have mentioned, it is objectionable in the "deep interior" regions, since it there admits closed timelike curves (CTCs), as does the Goedel lambdadust. These CTCs are problematical.' C. Hillman 1-05-2007 'tipping'

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# Topology of closed timelike curves (CTC)

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