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Related papers: Physical and Stable Closed Timelike Curves

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We consider Neveu-Schwarz pp-waves with spacetime supersymmetry. Upon compactification of a spacelike direction, these backgrounds develop Closed Null Curves (CNCs) and Closed Timelike Curves (CTCs), and are U-dual to supersymmetric Godel…

High Energy Physics - Theory · Physics 2009-11-10 Daniel Brace , Carlos A. R. Herdeiro , Shinji Hirano

Generalized quantum mechanics is used to examine a simple two-particle scattering experiment in which there is a bounded region of closed timelike curves (CTCs) in the experiment's future. The transitional probability is shown to depend on…

High Energy Physics - Theory · Physics 2009-10-30 Seth Rosenberg

We investigate vacuum solutions of Einstein's equation for a universe with an S^1 topology of time. Such a universe behaves like a time-machine and has geodesics which coincide with closed time-like curves (CTCs). A system evolving along a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Moninder Singh Modgil , Deshdeep Sahdev

Many results have been recently obtained regarding the power of hypothetical closed time-like curves (CTCs) in quantum computation. Here we show that the one-way model of measurement-based quantum computation encompasses in a natural way…

Quantum Physics · Physics 2011-01-27 Raphael Dias da Silva , Ernesto F. Galvao , Elham Kashefi

We apply the reduced radial gauge to give the general solution of the metric in 2+1 dimensions in term of quadratures. It allows a complete controll on the support of the source. We use the result to prove that for a general stationary…

General Relativity and Quantum Cosmology · Physics 2007-05-23 P. Menotti , D. Seminara

We examine some variants of computation with closed timelike curves (CTCs), where various restrictions are imposed on the memory of the computer, and the information carrying capacity and range of the CTC. We give full characterizations of…

Computational Complexity · Computer Science 2014-01-29 A. C. Cem Say , Abuzer Yakaryilmaz

It is shown explicitly that when the characteristic vector field that defines a Godel-type metric is also a Killing vector, there always exist closed timelike or null curves in spacetimes described by such a metric. For these geometries,…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Reinaldo J. Gleiser , Metin Gurses , Atalay Karasu , Ozgur Sarioglu

General relativity predicts the existence of closed timelike curves (CTCs), along which an object could travel to its own past. A consequence of CTCs is the failure of determinism, even for classical systems: one initial condition can…

Quantum Physics · Physics 2021-05-20 Lachlan G. Bishop , Fabio Costa , Timothy C. Ralph

We study the question of what is computable by Turing machines equipped with time travel into the past; i.e., with Deutschian closed timelike curves (CTCs) having no bound on their width or length. An alternative viewpoint is that we study…

We introduce a general categorical framework to reason about quantum theory and other process theories living in spacetimes where Closed Timelike Curves (CTCs) are available, allowing resources to travel back in time and provide…

Quantum Physics · Physics 2019-02-04 Nicola Pinzani , Stefano Gogioso , Bob Coecke

The existence of time machines, understood as spacetime constructions exhibiting physically realised closed timelike curves (CTCs), would raise fundamental problems with causality and challenge our current understanding of classical and…

General Relativity and Quantum Cosmology · Physics 2009-11-07 G. M. Shore

Notoriously, the Einstein equations of general relativity have solutions in which closed timelike curves (CTCs) occur. On these curves time loops back onto itself, which has exotic consequences. However, in order to make time travel stories…

General Relativity and Quantum Cosmology · Physics 2021-05-26 Ruward A. Mulder , Dennis Dieks

The existence and stability under linear perturbations of closed timelike geodesics (CTGs) in Bonnor-Ward spacetime is studied in some detail. Regions where the CTG exist and are linearly stable are exhibited.

General Relativity and Quantum Cosmology · Physics 2008-11-26 V. M. Rosa , P. S. Letelier

We discuss plane wave backgrounds of string theory and their relation to Goedel-like universes. This involves a twisted compactification along the direction of propagation of the wave, which induces closed timelike curves. We show, however,…

High Energy Physics - Theory · Physics 2014-11-18 D. Brecher , P. A. DeBoer , D. C. Page , M. Rozali

The motion of particles on spherical $1 + 3$ dimensional spacetimes can, under some assumptions, be described by the curves on a 2-dimensional manifold, the optical and Jacobi manifolds for null and timelike curves, respectively. In this…

General Relativity and Quantum Cosmology · Physics 2022-08-01 Pedro V. P. Cunha , Carlos A. R. Herdeiro , João P. A. Novo

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…

Quantum Physics · Physics 2008-11-26 Dave Bacon

We consider the region of closed timelike curves (CTC's) in three-dimensional flat Lorentz spacetimes. The interest in this global geometrical feature goes beyond the purely mathematical. Such spacetimes may be considered lower-dimensional…

Differential Geometry · Mathematics 2009-11-07 Virginie Charette , Todd A. Drumm , Dieter Brill

The theory of general relativity predicts the existence of closed time-like curves (CTCs), which theoretically would allow an observer to travel back in time and interact with their past self. This raises the question of whether this could…

Quantum Physics · Physics 2026-05-26 Germain Tobar , Fabio Costa

Closed Timelike Curves (CTCs) are intriguing relativistic objects that allow for time travel to the past and can be used as computational resources. In Deutschian Closed Timelike Curves (D-CTCs), due to the monogamy of entanglement,…

Quantum Physics · Physics 2018-10-11 Soumik Ghosh , Arnab Adhikary , Goutam Paul

Closed timelike curves (CTCs) appear in many solutions of the Einstein equation, even with reasonable matter sources. These solutions appear to violate causality and so are considered problematic. Since CTCs reflect the global properties of…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Sergei Slobodov