Results 31 to 40 of about 9,774 (177)
Cauchy problem in spacetimes with closed timelike curves [PDF]
Physical Review D, 1990 The laws of physics might permit the existence, in the real Universe, of closed timelike curves (CTC’s). Macroscopic CTC’s might be a semiclassical consequence of Planck-scale, quantum gravitational, Lorentzian foam, if such foam exists. If CTC’s are permitted, then the semiclassical laws of physics (the laws with gravity classical and other fields ...
Friedman, John +6 more
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Strings in irrelevant deformations of AdS3 /CFT2
Journal of High Energy Physics, 2020 We generalize our recent analysis [1] of probe string dynamics to the case of general single-trace T T ¯ , J T ¯ $$ T\overline{T},J\overline{T} $$ and T J ¯ $$ T\overline{J} $$ deformations.
Soumangsu Chakraborty +2 more
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Quantum Computational Complexity in the Presence of Closed Timelike Curves
, 2003 Quantum computation with quantum data that can traverse closed timelike curves represents a new physical model of computation. We argue that a model of quantum computation in the presence of closed timelike curves can be formulated which represents a ...
A. Kitaev +14 more
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Chronology protection implementation in analogue gravity
European Physical Journal C: Particles and Fields, 2022 Analogue gravity systems offer many insights into gravitational phenomena, both at the classical and at the semiclassical level. The existence of an underlying Minkowskian structure (or Galilean in the non-relativistic limit) in the laboratory has been ...
Carlos Barceló +3 more
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A substrate for brane shells from T T ¯ $$ T\overline{T} $$
Journal of High Energy Physics, 2021 A solvable current-current deformation of the worldsheet theory of strings on AdS3 has been recently conjectured to be dual to an irrelevant deformation of the spacetime orbifold CFT, commonly referred to as single-trace T T ¯ $$ T\overline{T} $$ . These
Jeremias Aguilera-Damia +2 more
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KINKS, ENERGY CONDITIONS AND CLOSED TIMELIKE CURVES [PDF]
International Journal of Modern Physics D, 2000 A link between the possibility of extending a geodesically incomplete kinked spacetime to a spacetime which is geodesically complete and the energy conditions is discussed for the case of a cylindrically-symmetric spacetime kink. It is concluded that neither the strong nor the weak energy condition can be satisfied in the four-dimensional example ...
openaire +2 more sources
Closed time-like curves in f(R,A) modified gravity theory
Nuclear Physics BIn this manuscript, we investigate solutions that allow closed time-like curves (CTCs) in general relativity (GR) within the framework of a modified gravity theory. We consider here an alternative theory recently proposed in gravity theories known as f(R,
F. Ahmed, J.C.R. de Souza, A.F. Santos
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On the occurrence of Closed Timelike Curves and the observer’s point of view
EPJ Web of Conferences, 2013 The existence of Closed Timelike Curves (CTCs) in a generic spacetime is often associated with a non-physical choice of coordinates and can be cured by limiting the admissibility of such coordinates.
Bini Donato, Geralico Andrea
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Journal of High Energy Physics, 2022 We generate a class of string backgrounds by a sequence of TsT transformations of the NS1-NS5 system that we argue are holographically dual to states in a single-trace T T ¯ $$ T\overline{T} $$ + J T ¯ $$ J\overline{T} $$ + T J ¯ $$ T\overline{J ...
Luis Apolo, Wei Song
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Discrete mechanics, “time machines” and hybrid systems
EPJ Web of Conferences, 2013 Modifying the discrete mechanics proposed by T.D. Lee, we construct a class of discrete classical Hamiltonian systems, in which time is one of the dynamical variables.
Elze Hans-Thomas
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