Results 51 to 60 of about 222 (175)
Axion Black Hole Solution in Non‐Metricity Gravity
Fortschritte der Physik, Volume 74, Issue 2, February 2026.Abstract A static, spherically symmetric black hole solution in symmetric teleparallel (non‐metricity) gravity sourced by an axion field is constructed. Starting from the modified field equations, exact configurations are obtained characterized by the mass M$M$ and an axion–geometry coupling β$\beta$, with temporal metric function A(r)=1−2Mr+βr$A(r)=1-\
A. Eid, G.G.L. Nashed
wiley +1 more source
Advances in High Energy Physics, 2020 In this paper, we present a type D, nonvanishing cosmological constant, vacuum solution of Einstein’s field equations, extension of an axially symmetric, asymptotically flat vacuum metric with a curvature singularity.
Faizuddin Ahmed +2 more
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Warp drives and closed timelike curves
Classical and Quantum GravityAbstract It is commonly accepted that superluminal travel may be used to facilitate time travel. This is a purely special-relativistic argument, using the fact that for observers in two frames of reference, separated by a spacelike interval, the non-causal (spacelike) future of one observer includes part of the causal past of the other ...
Barak Shoshany, Ben Snodgrass
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Nonlinearity in quantum theory and closed timelike curves [PDF]
Physical Review D, 1995 17 pages plain TeX, DAMTP R/94 ...
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Rigidity of anti‐de Sitter (2+1)‐spacetimes with convex boundary near the Fuchsian locus
Journal of the London Mathematical Society, Volume 113, Issue 2, February 2026.Abstract We prove that globally hyperbolic compact anti‐de Sitter (2+1)‐spacetimes with a strictly convex spacelike boundary that is either smooth or polyhedral and whose holonomy is close to Fuchsian are determined by the induced metric on the boundary.
Roman Prosanov, Jean‐Marc Schlenker
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Closed Timelike Curves Re-Examined
, 2004 17 pages, 6 postscript ...
Cooperstock, F. I., Tieu, S.
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Fortschritte der Physik, Volume 73, Issue 9-10, October 2025.Abstract The unification of conformal and fuzzy gravities with internal interactions is based on the facts that i) the tangent group of a curved manifold and the manifold itself do not necessarily have the same dimensions and ii) both gravitational theories considered here have been formulated in a gauge theoretic way.
Gregory Patellis +3 more
wiley +1 more source
Image of quantum improved regular kerr black hole and parameter constraints from EHT observations
European Physical Journal C: Particles and FieldsQuantum Improved Regular Kerr (QIRK) black hole is a rotating regular black hole model constructed based on the asymptotic safety method. The model eliminates the ring singularity and prevents the formation of closed timelike curves, while retaining well-
Li-Ming Cao, Long-Yue Li, Xia-Yuan Liu
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Axially Symmetric Null Dust Space-Time, Naked Singularity, and Cosmic Time Machine
Advances in High Energy Physics, 2017 We present a gravitational collapse null dust solution of the Einstein field equations. The space-time is regular everywhere except on the symmetry axis where it possesses a naked curvature singularity and admits one parameter isometry group, a generator
Faizuddin Ahmed
doaj +1 more source
Unitarity in the presence of closed timelike curves [PDF]
Physical Review D, 2006 We conjecture that, in certain cases, quantum dynamics is consistent in the presence of closed timelike curves. We consider time dependent orbifolds of three dimensional Minkowski space describing, in the limit of large AdS radius, BTZ black holes inside the horizon.
Cornalba, Lorenzo, Costa, Miguel S.
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