Non-Causal Spacetimes  

In General > s.a. causality conditions; causality violations [including time machines].
* Consequences: If closed timelike curves existed, quantum computers would be no more powerful than classical computers.
@ General references: Tipler PRD(74), PRL(76); Penrose in(79); Thorne in(91); Deser & Steif gq/92 [3D results]; Blau AJP(98)mar [and topology change]; Romero & Torres MPLA(01)gq [consistency]; Garay & González-Díaz GRG(01) [and quantum gravity]; Bonnor IJMPD(03)gq/02 [conceptual]; Lobo & Crawford gq/02-conf [rev]; Shore IJMPA(03)gq/02 [rev]; Susskind gq/05 [unlikely], rebuttal gq/05; Monroe FP(08)gq/06 [and topology]; Bonnor GRG(09) [size of region for spinning bodies]; Lobo a1008-in; Tippett & Tsang a1310 [for lay readers].
@ Paradoxes: Krasnikov PRD(97)gq/96, PRD(02)gq/01; Dowe PhSc(07)dec; Hauser & Shoshany PRD(20)-a1911 [resolutions]; Rovelli a1912 [and the physics of irreversible phenomena]; > s.a. causality violations in quantum theory; Grandfather Paradox.
@ In other theories of gravity: Rebouças & Santos a1007-MG12 [in f(R) gravity]; > s.a. torsion in physical theories [f(T) theories].

Examples, Special Types > s.a. gödel spacetime; Misner Space; types of spacetimes [3D flat]; wormholes [including Krasnikov tube].
@ Examples: Chamblin et al PRD(94), Yurtsever GRG(05)gq/94 [Politzer spacetime]; Caldarelli et al JHEP(01) [in AdS5]; Bonnor CQG(02) [asymptotically flat example], Rebouças & Teixeira IJMPA(98)gq [Kaluza-Klein theory]; Olum & Everett FPL(05) [re circulating light beam]; Bonnor & Steadman GRG(05) [Einstein-Maxwell]; Rosa & Letelier in(10)-a0706 [cylindrical with spinning sources, stability of closed timelike curves]; Grøn & Johannesen a1005 [stationary cylindrically symmetric with matter]; Pavan PhD(10)-a1005 [cylindrically symmetric, stationary]; Prezens a1008 [Kramer-Neugebauer double Kerr solution]; Sarma et al a1203, AP(13) [vacuum spacetime locally isometric to a plane-wave spacetime with closed null geodesics]; Ho & Weiler MPLA(13)-a1209 [model that avoids pathologies]; Tippett & Tsang a1310 [and time travel]; Ahmed CTP(17)-a1712 [type-D, non-vacuum spcetime]; Fermi & Pizzocchero CQG(18)-a1803, Fermi a1812-proc [with geodesic CTCs].
@ Initial-value problem: Friedman & Morris PRL(91), in(91) [massless wave equation]; Fewster et al PRD(96)gq; Friedman gq/04-in [rev]; Aref'eva et al TMP(08) [waves]; Dolanský & Krtouš PRD(10)-a1011 [classical billiard].
@ Chronology protection: Hawking PRD(92); Visser PRD(93), NPB(94)ht/93; Cassidy & Hawking PRD(98)ht/97 [models]; Huang PRD(99)ht/02 [in Gödel spacetime]; Hiscock gq/00; Visser gq/02-conf [rev]; Friedman & Higuchi AdP(06)-a0801 [rev]; Monroe gq/06 [censorship]; Segre gq/06 [comment]; Raeymaekers et al JHEP(10)-a0911 [and unitarity, via the AdS/CFT correspondence]; Raeymaekers JHEP(11)-a1106, JPCS(12)-a1111 [stationary 3D spacetimes]; Czachor a1805 [interferometric analogue]; > s.a. wormholes.
@ And singularities: Maeda & Ishibashi PRD(97) [spatially compact].
@ And energy conditions: Ori PRL(91), PRL(93); Olum PRL(98)gq; Visser et al NPPS(00)gq/98; Baird gq/99; Sengupta PRD(18)-a1805.
@ And computation: Durham a0803 [and quantum information]; Andréka et al PPL(12)-a1105 [relativistic computation]; Brun & Wilde FP(17)-a1504 [information-processing protocols and simulations]; Aaronson et al a1609 [Turing machines equipped with time travel into the past]; Bartkiewicz et al PRA(19)-a1711 [and the second law of thermodynamics]; > s.a. quantum computers.
@ Related topics: Cooperstock & Tieu gq/04, FP(05) [misconceived article?]; Hadley gq/06-MGXI [and quantum theory]; Ralph a1107; Pienaar et al PRA(11)-a1110 [and quantum field theory]; Yuan et al NPJQI(15)-a1412 [benefits of closed timelike curves without breaking causality]; Minguzzi CQG(16)-a1603 [boundary of the chronology-violating set]; Mulder & Dieks a1704 [determinism and indeterminism]; > s.a. klein-gordon fields; locality [relative locality].

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