Is Complex General Relativity the Key to Understanding Naked Singularities?

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Discussion Overview

The discussion revolves around the concept of complex general relativity and its potential implications for understanding naked singularities. Participants explore the theoretical framework of general relativity (GR) when extended to complex values, particularly in relation to black hole event horizons and extremal conditions.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that complex general relativity could provide insights into naked singularities, as classical GR is limited to real manifolds.
  • Another participant references a work by Domenico Giulini that discusses complex general relativity and its field equations derived from a variational principle.
  • A participant expresses interest in a formulation of GR using complex metrics or connections, specifically in relation to Kerr or Kerr-Newman black holes and their behavior in extremal limits.
  • There is a suggestion that the complexity of formulating GR on a complex manifold may explain why few have pursued this line of inquiry beyond Ashtekar's work.
  • One participant shares a link to another paper by Esposito, indicating ongoing exploration in the field.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the viability or implications of complex general relativity. Multiple viewpoints exist regarding its potential and the challenges associated with it.

Contextual Notes

Participants note the limitations of existing formulations and the need for further exploration into the reality conditions and geometric interpretations of complex variables in GR.

Jim
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Complex (not because its difficult !), but because certain elements of classical, real GR
are allowed to assume complex (real + imag parts) values, such as the metric or connexion.
I am wondering if anyone is aware of any legitimate work going on in this area ??
I have already been shanghied by a crackpot's book (blaha's) only to find out that he has never published on this subject either on arxiv or ref.'d journals.
The subject is fascinating simply because black hole event horizons become complexified if they exceed `extreme' classification, and go over into naked singularities (NS).
Since GR is limited to a real manifold, the problem of NS might become tractable in a complex version of GR...
Any thoughts, references ?
 
Physics news on Phys.org
http://arxiv.org/abs/gr-qc/9312032
Ashtekar Variables in Classical General Realtivity
Domenico Giulini
"Chapter three considers complex General Relativity and shows how its field equations can be obtained from a variational principle involving only the self dual part of the connection. In chapter four the (3+1)-decomposition is presented in as much detail as seemed necessary for an audience that does not consist entirely of canonical relativists. It is then applied to complex General Relativity in chapter five, where for the first time Ashtekar’s connection variables are introduced. The Hamiltonian of complex General Relativity is presented in terms of connection variables. In chapter six the constraints that follow from the variational principle are analyzed and their Poisson brackets are presented. In chapter seven we discuss the reality conditions that have to be imposed by hand to select real solutions, and briefly sketch the geometric interpretation of the new variables. In chapter 8 we indicate how the Hamiltonian has to be amended by surface integrals in the case of open initial data hypersurfaces with asymptotically flat data. It ends with a demonstration of the positivity of the mass at spatial infinity for maximal hypersurfaces."
 
Very nice pedagogical intro to LQG, Atyy.
However, I was not thinking of LQG, but just a generalization of the GR field eqs, via either a complex metric or connexion. In particular, I am interested in learning of such a formulation which is then applied to either Kerr or Kerr-Newman BHs, and whether in the extremal limits, such BHs morph into naked singularities. I suspect there is something terribly intractable about formulating GR on a complex (3+1) manifold, or many people other than Ashtekar would've attempted it by now, in an attempt to generalize GR.
 

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