176:
435:(time machines) can only be consistent with the universal laws of physics, and thus only self-consistent events can occur. Anything a time traveler does in the past must have been part of history all along, and the time traveler can never do anything to prevent the trip back in time from happening, since this would represent an inconsistency. The authors concluded that time travel need not lead to unresolvable paradoxes, regardless of what type of object was sent to the past.
383:, which are described as leaving no trace when they disappear. Lossev and Novikov allowed the term "Jinn" to cover both objects and information with the reflexive origin; they called the former "Jinn of the first kind", and the latter "Jinn of the second kind". They point out that an object making circular passage through time must be identical whenever it is brought back to the past, otherwise it would create an inconsistency; the
185:
conception of oneself. If the time traveler were not born, then it would not be possible for the traveler to undertake such an act in the first place. Therefore, the ancestor lives to offspring the time traveler's next-generation ancestor, and eventually the time traveler. There is thus no predicted outcome to this. Consistency paradoxes occur whenever changing the past is possible. A possible resolution is that a time traveller
315:, arguing that the possibility of creating a contradiction rules out time travel to the past entirely. However, some philosophers and scientists believe that time travel into the past need not be logically impossible provided that there is no possibility of changing the past, as suggested, for example, by the
512:, even if it is not built up by quantum systems. Allen Everett has also argued that even if Deutsch's approach is correct, it would imply that any macroscopic object composed of multiple particles would be split apart when traveling back in time, with different particles emerging in different worlds.
354:
writes that these bootstrap paradoxes – information or an object looping through time – are the same; the primary apparent paradox is a physical system evolving into a state in a way that is not governed by its laws. He does not find these paradoxical and attributes problems regarding the validity of
269:
and free will by allowing for "perfect predictors": if perfect predictors of the future exist, for example if time travel exists as a mechanism for making perfect predictions, then perfect predictions appear to contradict free will because decisions apparently made with free will are already known to
507:
with a negative delay—backward time travel—produces only self-consistent solutions, and the chronology-violating region imposes constraints that are not apparent through classical reasoning. However
Deutsch's self-consistency condition has been demonstrated as capable of being fulfilled to arbitrary
459:
showed that for certain initial trajectories of the billiard ball, there could be an infinite number of self-consistent solutions. It is plausible that there exist self-consistent extensions for every possible initial trajectory, although this has not been proven. The lack of constraints on initial
454:
referred to this problem as "Polchinski's paradox". Thorne and two of his students at
Caltech, Fernando Echeverria and Gunnar Klinkhammer, went on to find a solution that avoided any inconsistencies, and found that there was more than one self-consistent solution, with slightly different angles for
179:
Top: original billiard ball trajectory. Middle: the billiard ball emerges from the future, and delivers its past self a strike that averts the past ball from entering the time machine. Bottom: The billiard ball never enters the time machine, giving rise to the paradox, putting into question how its
148:
as an example involving an object with no origin: an old woman gives a watch to a playwright who later travels back in time and meets the same woman when she was young, and gives her the same watch that she will later give to him. An example of information which "came from nowhere" is in the movie
184:
The consistency paradox or grandfather paradox occurs when the past is changed in any way, thus creating a contradiction. A common example given is traveling to the past and intervening with the conception of one's ancestors (such as causing the death of the parent beforehand), thus affecting the
392:
systems, a Jinnee could interact with its environment in such a way as to regain "lost" entropy. They emphasize that there is no "strict difference" between Jinn of the first and second kind. Krasnikov equivocates between "Jinn", "self-sufficient loops", and "self-existing objects", calling them
492:
of quantum mechanics that involves time travelers arriving in a different universe than the one from which they came; it has been argued that, since travelers arrive in a different universe's history and not their history, this is not "genuine" time travel. Stephen
Hawking has argued for the
387:
seems to require that the object tends to a lower energy state throughout its history, and such objects that are identical in repeating points in their history seem to contradict this, but Lossev and
Novikov argued that since the second law only requires entropy to increase in
295:
that changing the past results in a logical contradiction. If it is necessarily true that the past happened in a certain way, then it is false and impossible for the past to have occurred in any other way. A time traveler would not be able to change the past from the way it
471:
solution, and supposes that there are far more damaging implications of time travel. Krasnikov similarly finds no inherent fault in causal loops but finds other problems with time travel in general relativity. Another conjecture, the
213:
The grandfather paradox encompasses any change to the past, and it is presented in many variations, including killing one's past self. Both the "retro-suicide paradox" and the "grandfather paradox" appeared in letters written into
82:
Temporal paradoxes fall into three broad groups: bootstrap paradoxes, consistency paradoxes, and
Newcomb's paradox. Bootstrap paradoxes violate causality by allowing future events to influence the past and cause themselves, or
497:, that even if the MWI is correct, we should expect each time traveler to experience a single self-consistent history so that time travelers remain within their world rather than traveling to a different one.
127:, or a "predestination paradox" is a paradox of time travel that occurs when any event, such as an action, information, an object, or a person, ultimately causes itself, as a consequence of either
393:"lions" or "looping or intruding objects", and asserts that they are no less physical than conventional objects, "which, after all, also could appear only from either infinity or a singularity."
239:
Physicist John
Garrison et al. give a variation of the paradox of an electronic circuit that sends a signal through a time machine to shut itself off, and receives the signal before it sends it.
450:
at just the right angle such that it will be sent back in time and collides with its earlier self, knocking it off course, which would stop it from entering the wormhole in the first place.
307:
Consideration of the grandfather paradox has led some to the idea that time travel is by its very nature paradoxical and therefore logically impossible. For example, the philosopher
278:
power, and could be the result of other "infallible foreknowledge" mechanisms. Problems arising from infallibility and influencing the future are explored in
Newcomb's paradox.
1442:
107:" is sometimes referred to as a causal loop, but although they appear similar, causal loops are unchanging and self-originating, whereas time loops are constantly resetting.
142:, but their origin cannot be determined. The notion of objects or information that are "self-existing" in this way is often viewed as paradoxical. Everett gives the movie
220:
in the 1920s. Another variant of the grandfather paradox is the "Hitler paradox" or "Hitler's murder paradox", in which the protagonist travels back in time to murder
167:
Smeenk uses the term "predestination paradox" to refer specifically to situations in which a time traveler goes back in time to try to prevent some event in the past.
1565:
138:
Backward time travel would allow information, people, or objects whose histories seem to "come from nowhere". Such causally looped events then exist in
57:
or other foreknowledge of the future. While the notion of time travel to the future complies with the current understanding of physics via relativistic
2329:
91:." Consistency paradoxes, on the other hand, are those where future events influence the past to cause an apparent contradiction, exemplified by the
61:, temporal paradoxes arise from circumstances involving hypothetical time travel to the past – and are often used to demonstrate its impossibility.
95:, where a person travels to the past to prevent the conception of one of their ancestors, thus eliminating all the ancestor's descendants.
2087:
Tolksdorf, Juergen; Verch, Rainer (2021). "The D-CTC condition is generically fulfilled in classical (non-quantum) statistical systems".
1661:
Friedman, John; Morris, Michael S.; Novikov, Igor D.; Echeverria, Fernando; Klinkhammer, Gunnar; Thorne, Kip S.; Yurtsever, Ulvi (1990).
343:
view, in which time is just another dimension like space, with all events at all times being fixed within this four-dimensional "block".
88:
2501:
2015:
1111:
Garrison, J.C.; Mitchell, M.W.; Chiao, R.Y.; Bolda, E.L. (August 1998). "Superluminal
Signals: Causal Loop Paradoxes Revisited".
30:
This article is about apparent contradictions in the concept of time travel. For the controversy over the origin of birds, see
17:
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791:
759:
420:
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2140:
Everett, Allen (2004). "Time travel paradoxes, path integrals, and the many worlds interpretation of quantum mechanics".
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and foreknowledge of future events. All of these are sometimes referred to individually as "causal loops." The term "
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521:
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461:
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Novikov's views are not widely accepted. Visser views causal loops and
Novikov's self-consistency principle as an
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340:
31:
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464:; the constraints on the chronology-violating region might prove to be paradoxical, but this is not yet known.
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Even without knowing whether time travel to the past is physically possible, it is possible to show using
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778:
Smeenk, Chris; Wüthrich, Christian (2011), "Time Travel and Time
Machines", in Callender, Craig (ed.),
489:
2203:
1278:
408:
364:
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to assert that time might itself be a sort of illusion. He suggests something along the lines of the
331:
Consideration of the possibility of backward time travel in a hypothetical universe described by a
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happen. Doing something that did not happen results in a contradiction. This is referred to as the
144:
974:
816:
1888:
Bangs, Crunches, Whimpers, and Shrieks: Singularities and Acausalities in Relativistic Spacetimes
415:
would be possible without the generation of paradoxes. According to this hypothesis, even though
1762:"An Example of a New Type of Cosmological Solution of Einstein's Field Equations of Gravitation"
561:
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1476:
713:
571:
432:
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319:. Dowden revised his view after being convinced of this in an exchange with the philosopher
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1865:
1838:"Billiard balls in wormhole spacetimes with closed timelike curves: Classical theory"
1816:
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232:. Rather than necessarily physically preventing time travel, the action removes any
175:
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2167:
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1975:
1963:
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1735:
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351:
155:, in which a 23rd-century engineer travels back in time, and gives the formula for
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53:, an apparent contradiction, or logical contradiction associated with the idea of
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stems from the apparent contradictions that stem from the assumptions of both
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320:
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84:
58:
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Wolpert, D. H.; Benford, G. (June 2013). "The lesson of Newcomb's paradox".
336:
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1837:
1694:
1662:
275:
225:
221:
1708:
Krasnikov, S. (2002), "No time machines in classical general relativity",
355:
time travel to other factors in the interpretation of general relativity.
2435:
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1125:
576:
424:
412:
292:
180:
older self could ever emerge from the time machine and divert its course.
132:
54:
1212:
2344:
1936:
Visser, Matt (15 April 1997). "Traversable wormholes: The Roman ring".
1913:
Time Machines: Time Travel in Physics, Metaphysics, and Science Fiction
1806:
1330:
1299:
1251:
1053:
Time Machines: Time Travel in Physics, Metaphysics, and Science Fiction
451:
236:
for the travel, along with any knowledge that the reason ever existed.
2154:
1950:
1722:
1521:
1380:
Beyond Experience: Metaphysical Theories and Philosophical Constraints
858:
848:
Lobo, Francisco (2003). "Time, Closed Timelike Curves and Causality".
685:
657:
2402:
2387:
2283:
1566:"The Jinn of the time machine: non-trivial self-consistent solutions"
671:
Francisco Lobo (2003). "Time, Closed Timelike Curves and Causality".
566:
546:
266:
139:
104:
100:
76:
2044:(15 November 1991). "Quantum mechanics near closed timelike lines".
1291:
71:"Causal loop" redirects here. For the cause and effect diagram, see
2382:
2101:
1398:(New ed.). Oxford: Oxford University Press. pp. 368–369.
1191:
541:
447:
1003:(2nd ed.). Cambridge, Massachusetts: MIT Press. p. 116.
488:
The interacting-multiple-universes approach is a variation of the
431:
that lead back to the same point in spacetime, physics in or near
300:
but would only act in a way that is already consistent with what
50:
1444:
A World Without Time: The Forgotten Legacy of Godel and Einstein
627:(1st Scribner hardcover ed.). New York: Scribner. pp.
1090:(1st ed.). Minnesota: Llewellyn Publications. p. 23.
265:
principle. The thought experiment is often extended to explore
2188:
476:, suggests that every closed timelike curve passes through an
1836:
Echeverria, Fernando; Gunnar Klinkhammer; Kip Thorne (1991).
455:
the glancing blow in each case. Later analysis by Thorne and
380:
1988:
442:
considered a potentially paradoxical situation involving a
376:
1663:"Cauchy problem in spacetimes with closed timelike curves"
1110:
1001:
Asymmetries in Time: Problems in the Philosophy of Science
852:. NATO Science Series II. Vol. 95. pp. 289–296.
1276:(1988). "Tachyons, Time Travel, and Divine Omniscience".
508:
precision by any system subject to the laws of classical
159:
to the 20th-century engineer who supposedly invented it.
480:, which prevents such causal loops from being observed.
1168:. Springer International Publishing. pp. 335–336.
396:
1982:
850:
The Nature of Time: Geometry, Physics and Perception
460:
conditions only applies to spacetime outside of the
1989:Frank Arntzenius; Tim Maudlin (December 23, 2009),
1915:. American Institute of Physics. pp. 345–352.
1881:
1879:
972:
1640:. New York, New York: W. W. Norton & Company.
1356:. Oxford University Press. pp. 356, 370–375.
1050:
1017:
895:(1. publ. ed.). New York: Routledge. p.
1507:Krasnikov, S. (2001), "The time travel paradox",
968:
966:
750:. Chicago: University of Chicago Press. pp.
2473:
1876:
1502:
1500:
1498:
1496:
588:
1383:, University of Toronto Press, pp. 226–227
2086:
1188:
963:
947:Lorentzian Wormholes: From Einstein to Hawking
777:
670:
257:showing an apparent contradiction between the
27:Theoretical paradox resulting from time travel
2204:
1629:
1627:
1625:
1564:Lossev, Andrei; Novikov, Igor (15 May 1992).
1563:
1559:
1557:
1555:
1493:
1418:
1376:
363:A 1992 paper by physicists Andrei Lossev and
2007:
1654:
1315:"Divine Foreknowledge and Newcomb's Paradox"
1236:"Divine Foreknowledge and Newcomb's Paradox"
745:
618:
616:
407:The self-consistency principle developed by
2133:
1057:(2nd ed.). New York: Springer-Verlag.
707:
311:made this sort of argument in the textbook
2211:
2197:
1835:
1622:
1552:
1042:
949:. New York: Springer-Verlag. p. 213.
622:
2153:
2100:
1949:
1801:
1799:
1797:
1785:
1721:
1707:
1520:
1506:
1124:
857:
780:The Oxford Handbook of Philosophy of Time
741:
739:
737:
735:
733:
684:
613:
346:
162:
2308:
1660:
1440:
1434:
1023:
773:
771:
594:
462:chronology-violating region of spacetime
358:
286:
174:
2139:
2040:
2034:
2013:
1393:
1351:
1182:
1083:
998:
992:
810:
808:
806:
804:
802:
375:. This terminology was inspired by the
281:
14:
2474:
1935:
1885:
1805:
1794:
1633:
1447:. New York: Basic Books. p. 134.
1412:
1370:
944:
843:
841:
839:
837:
746:Everett, Allen; Roman, Thomas (2012).
730:
411:expresses one view as to how backward
170:
115:A bootstrap paradox, also known as an
2192:
1910:
1759:
1312:
1272:
1233:
1163:
1048:
924:. New York : Routledge. p. 204.
814:
768:
708:Jones, Matthew; Ormrod, Joan (2015).
483:
367:labeled such items without origin as
1474:
1468:
847:
799:
651:
242:
110:
1995:Stanford Encyclopedia of Philosophy
1030:Stanford Encyclopedia of Philosophy
979:Stanford Encyclopedia of Philosophy
919:
890:
834:
821:Stanford Encyclopedia of Philosophy
782:, Oxford University Press, p.
664:
601:Stanford Encyclopedia of Philosophy
89:pull oneself up by one's bootstraps
24:
2244:Novikov self-consistency principle
1815:. W. W. Norton. pp. 509–513.
403:Novikov self-consistency principle
397:Novikov self-consistency principle
317:Novikov self-consistency principle
203:Novikov self-consistency principle
25:
2513:
1421:"Time Travel - Visiting the Past"
87:", which derives from the idiom "
2254:Quantum mechanics of time travel
2234:Chronology protection conjecture
1991:"Time Travel and Modern Physics"
1441:Yourgrau, Palle (4 March 2009).
557:Chronology protection conjecture
522:Quantum mechanics of time travel
495:chronology protection conjecture
326:
2218:
2080:
1929:
1904:
1829:
1753:
1701:
1387:
1345:
1306:
1266:
1227:
1157:
1104:
1077:
938:
913:
884:
274:does not necessarily involve a
32:temporal paradox (paleontology)
2502:Thought experiments in physics
1087:Time Travel: A New Perspective
1024:Jan Faye (November 18, 2015),
701:
645:
595:Jan Faye (November 18, 2015),
13:
1:
2350:Parallel universes in fiction
1710:Classical and Quantum Gravity
1143:10.1016/S0375-9601(98)00381-8
815:Smith, Nicholas J.J. (2013).
582:
152:Star Trek IV: The Voyage Home
2360:Philosophy of space and time
1313:Craig, William Lane (1987).
973:Nicholas J.J. Smith (2013).
710:Time Travel in Popular Media
532:Cosmic censorship hypothesis
474:cosmic censorship hypothesis
385:second law of thermodynamics
7:
1890:. Oxford University Press.
1740:10.1088/0264-9381/19/15/316
748:Time Travel and Warp Drives
515:
208:
75:. For the plot device, see
10:
2518:
2340:Many-worlds interpretation
2227:General terms and concepts
2172:10.1103/PhysRevD.69.124023
2119:10.1007/s10701-021-00496-z
1812:Black Holes and Time Warps
1593:10.1088/0264-9381/9/10/014
1539:10.1103/PhysRevD.65.064013
623:Klosterman, Chuck (2009).
490:many-worlds interpretation
400:
246:
70:
29:
2401:
2358:
2322:
2299:
2262:
2226:
2014:Hawking, Stephen (1999).
1787:10.1103/RevModPhys.21.447
1394:Dummett, Michael (1996).
1352:Dummett, Michael (1996).
1279:The Journal of Philosophy
1205:10.1007/s11229-011-9899-3
922:Arguing about Metaphysics
409:Igor Dmitriyevich Novikov
371:, with the singular term
2249:Self-fulfilling prophecy
2066:10.1103/PhysRevD.44.3197
1968:10.1103/PhysRevD.55.5212
1862:10.1103/PhysRevD.44.1077
1687:10.1103/PhysRevD.42.1915
1475:Holt, Jim (2005-02-21).
920:Rea, Michael C. (2009).
652:Ross, Kelley L. (1997).
224:before he can instigate
64:
1911:Nahin, Paul J. (1999).
1164:Nahin, Paul J. (2016).
1049:Nahin, Paul J. (1999).
893:Metaphysics: The Basics
714:McFarland & Company
654:"Time Travel Paradoxes"
270:the perfect predictor.
253:Newcomb's paradox is a
2413:closed timelike curves
2264:Time travel in fiction
2089:Foundations of Physics
2016:"Space and Time Warps"
1637:The New Time Travelers
1634:Toomey, David (2012).
1573:Class. Quantum Gravity
1419:Norman Swartz (1993).
1377:Norman Swartz (2001),
1084:Brennan, J.H. (1997).
999:Horwich, Paul (1987).
673:Nato Science Series II
572:Time travel in fiction
433:closed timelike curves
429:closed timelike curves
347:Physical impossibility
181:
163:Predestination paradox
18:Predestination paradox
2461:Traversable wormholes
2239:Closed timelike curve
1886:Earman, John (1995).
945:Visser, Matt (1996).
891:Rea, Michael (2014).
510:statistical mechanics
446:that is fired into a
359:Self-sufficient loops
287:Logical impossibility
178:
2272:Timelines in fiction
2022:on February 10, 2012
1760:Gödel, Kurt (1949).
1396:The Seas of Language
1354:The Seas of Language
1026:"Backward Causation"
660:on January 18, 1998.
597:"Backward Causation"
562:Münchhausen trilemma
282:Proposed resolutions
157:transparent aluminum
2309:Grandfather paradox
2164:2004PhRvD..69l4023E
2111:2021FoPh...51...93T
2058:1991PhRvD..44.3197D
1960:1997PhRvD..55.5212V
1854:1991PhRvD..44.1077E
1778:1949RvMP...21..447G
1732:2002CQGra..19.4109K
1679:1990PhRvD..42.1915F
1610:on 17 November 2015
1585:1992CQGra...9.2309L
1531:2002PhRvD..65f4013K
1274:Craig, William Lane
1135:1998PhLA..245...19G
868:2003ntgp.conf..289L
695:2003ntgp.conf..289L
625:Eating the Dinosaur
505:quantum computation
335:led famed logician
263:strategic dominance
171:Grandfather paradox
125:ontological paradox
121:information paradox
93:grandfather paradox
73:causal loop diagram
47:time travel paradox
2492:Physical paradoxes
2482:Temporal paradoxes
2407:general relativity
2330:Alternative future
2323:Parallel timelines
2301:Temporal paradoxes
2277:in science fiction
2148:(124023): 124023.
1331:10.1007/BF02455055
1252:10.1007/BF02455055
1166:Time Machine Tales
503:has proposed that
484:Parallel universes
417:general relativity
261:principle and the
255:thought experiment
182:
2469:
2468:
2421:Alcubierre metric
2335:Alternate history
2142:Physical Review D
2052:(10): 3197–3217.
2046:Physical Review D
1938:Physical Review D
1842:Physical Review D
1667:Physical Review D
1647:978-0-393-06013-3
1579:(10): 2309–2321.
1113:Physics Letters A
931:978-0-415-95826-4
906:978-0-415-57441-9
793:978-0-19-929820-4
761:978-0-226-22498-5
440:Joseph Polchinski
313:Logical Reasoning
249:Newcomb's paradox
243:Newcomb's paradox
197:do anything that
189:do anything that
145:Somewhere in Time
111:Bootstrap paradox
97:Newcomb's paradox
16:(Redirected from
2509:
2456:van Stockum dust
2368:Butterfly effect
2213:
2206:
2199:
2190:
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2038:
2032:
2031:
2029:
2027:
2018:. Archived from
2011:
2005:
2004:
2003:
2001:
1986:
1980:
1979:
1953:
1944:(8): 5212–5214.
1933:
1927:
1926:
1908:
1902:
1901:
1883:
1874:
1873:
1848:(4): 1077–1099.
1833:
1827:
1826:
1803:
1792:
1791:
1789:
1757:
1751:
1750:
1725:
1705:
1699:
1698:
1673:(6): 1915–1930.
1658:
1652:
1651:
1631:
1620:
1619:
1617:
1615:
1609:
1603:. Archived from
1570:
1561:
1550:
1549:
1524:
1504:
1491:
1490:
1488:
1487:
1472:
1466:
1465:
1463:
1461:
1438:
1432:
1431:
1429:
1428:
1416:
1410:
1409:
1391:
1385:
1384:
1374:
1368:
1367:
1349:
1343:
1342:
1310:
1304:
1303:
1270:
1264:
1263:
1231:
1225:
1224:
1199:(9): 1637–1646.
1186:
1180:
1179:
1161:
1155:
1154:
1128:
1126:quant-ph/9810031
1108:
1102:
1101:
1081:
1075:
1074:
1072:
1071:
1056:
1046:
1040:
1039:
1038:
1036:
1021:
1015:
1014:
996:
990:
989:
987:
985:
970:
961:
960:
942:
936:
935:
917:
911:
910:
888:
882:
881:
861:
845:
832:
831:
829:
827:
812:
797:
796:
775:
766:
765:
743:
728:
727:
705:
699:
698:
688:
668:
662:
661:
656:. Archived from
649:
643:
642:
620:
611:
610:
609:
607:
592:
552:Causal structure
352:Sergey Krasnikov
259:expected utility
117:information loop
39:temporal paradox
21:
2517:
2516:
2512:
2511:
2510:
2508:
2507:
2506:
2472:
2471:
2470:
2465:
2451:Tipler cylinder
2410:
2397:
2354:
2318:
2295:
2258:
2222:
2217:
2187:
2138:
2134:
2085:
2081:
2039:
2035:
2025:
2023:
2012:
2008:
1999:
1997:
1987:
1983:
1934:
1930:
1923:
1909:
1905:
1898:
1884:
1877:
1834:
1830:
1823:
1804:
1795:
1758:
1754:
1706:
1702:
1659:
1655:
1648:
1632:
1623:
1613:
1611:
1607:
1568:
1562:
1553:
1505:
1494:
1485:
1483:
1473:
1469:
1459:
1457:
1455:
1439:
1435:
1426:
1424:
1417:
1413:
1406:
1392:
1388:
1375:
1371:
1364:
1350:
1346:
1311:
1307:
1292:10.2307/2027068
1271:
1267:
1232:
1228:
1187:
1183:
1176:
1162:
1158:
1109:
1105:
1098:
1082:
1078:
1069:
1067:
1065:
1047:
1043:
1034:
1032:
1022:
1018:
1011:
997:
993:
983:
981:
971:
964:
957:
943:
939:
932:
918:
914:
907:
889:
885:
878:
846:
835:
825:
823:
813:
800:
794:
776:
769:
762:
744:
731:
724:
716:. p. 207.
706:
702:
669:
665:
650:
646:
639:
621:
614:
605:
603:
593:
589:
585:
518:
486:
423:that allow for
421:exact solutions
405:
399:
361:
349:
329:
289:
284:
251:
245:
217:Amazing Stories
211:
173:
165:
113:
80:
67:
35:
28:
23:
22:
15:
12:
11:
5:
2515:
2505:
2504:
2499:
2494:
2489:
2484:
2467:
2466:
2464:
2463:
2458:
2453:
2448:
2443:
2441:Krasnikov tube
2438:
2433:
2428:
2426:BTZ black hole
2423:
2417:
2415:
2399:
2398:
2396:
2395:
2393:Predestination
2390:
2385:
2380:
2375:
2370:
2364:
2362:
2356:
2355:
2353:
2352:
2347:
2342:
2337:
2332:
2326:
2324:
2320:
2319:
2317:
2316:
2311:
2305:
2303:
2297:
2296:
2294:
2293:
2292:
2291:
2281:
2280:
2279:
2268:
2266:
2260:
2259:
2257:
2256:
2251:
2246:
2241:
2236:
2230:
2228:
2224:
2223:
2216:
2215:
2208:
2201:
2193:
2186:
2185:
2132:
2079:
2042:Deutsch, David
2033:
2006:
1981:
1928:
1921:
1903:
1896:
1875:
1828:
1821:
1807:Thorne, Kip S.
1793:
1772:(3): 447–450.
1766:Rev. Mod. Phys
1752:
1700:
1653:
1646:
1621:
1551:
1492:
1481:The New Yorker
1477:"Time Bandits"
1467:
1453:
1433:
1411:
1404:
1386:
1369:
1362:
1344:
1325:(3): 331–350.
1305:
1286:(3): 135–150.
1265:
1246:(3): 331–350.
1234:Craig (1987).
1226:
1181:
1174:
1156:
1119:(1–2): 19–25.
1103:
1096:
1076:
1063:
1041:
1016:
1009:
991:
962:
955:
937:
930:
912:
905:
883:
876:
833:
798:
792:
767:
760:
729:
722:
700:
663:
644:
637:
612:
586:
584:
581:
580:
579:
574:
569:
564:
559:
554:
549:
544:
539:
537:Retrocausality
534:
529:
524:
517:
514:
485:
482:
457:Robert Forward
401:Main article:
398:
395:
360:
357:
348:
345:
328:
325:
309:Bradley Dowden
288:
285:
283:
280:
272:Predestination
247:Main article:
244:
241:
210:
207:
172:
169:
164:
161:
129:retrocausality
112:
109:
66:
63:
26:
9:
6:
4:
3:
2:
2514:
2503:
2500:
2498:
2495:
2493:
2490:
2488:
2485:
2483:
2480:
2479:
2477:
2462:
2459:
2457:
2454:
2452:
2449:
2447:
2444:
2442:
2439:
2437:
2434:
2432:
2429:
2427:
2424:
2422:
2419:
2418:
2416:
2414:
2408:
2404:
2400:
2394:
2391:
2389:
2386:
2384:
2381:
2379:
2376:
2374:
2371:
2369:
2366:
2365:
2363:
2361:
2357:
2351:
2348:
2346:
2343:
2341:
2338:
2336:
2333:
2331:
2328:
2327:
2325:
2321:
2315:
2312:
2310:
2307:
2306:
2304:
2302:
2298:
2290:
2287:
2286:
2285:
2282:
2278:
2275:
2274:
2273:
2270:
2269:
2267:
2265:
2261:
2255:
2252:
2250:
2247:
2245:
2242:
2240:
2237:
2235:
2232:
2231:
2229:
2225:
2221:
2214:
2209:
2207:
2202:
2200:
2195:
2194:
2191:
2181:
2177:
2173:
2169:
2165:
2161:
2156:
2155:gr-qc/0410035
2151:
2147:
2143:
2136:
2128:
2124:
2120:
2116:
2112:
2108:
2103:
2098:
2094:
2090:
2083:
2075:
2071:
2067:
2063:
2059:
2055:
2051:
2047:
2043:
2037:
2021:
2017:
2010:
1996:
1992:
1985:
1977:
1973:
1969:
1965:
1961:
1957:
1952:
1951:gr-qc/9702043
1947:
1943:
1939:
1932:
1924:
1922:0-387-98571-9
1918:
1914:
1907:
1899:
1897:0-19-509591-X
1893:
1889:
1882:
1880:
1871:
1867:
1863:
1859:
1855:
1851:
1847:
1843:
1839:
1832:
1824:
1822:0-393-31276-3
1818:
1814:
1813:
1808:
1802:
1800:
1798:
1788:
1783:
1779:
1775:
1771:
1767:
1763:
1756:
1749:
1745:
1741:
1737:
1733:
1729:
1724:
1723:gr-qc/0111054
1719:
1715:
1711:
1704:
1696:
1692:
1688:
1684:
1680:
1676:
1672:
1668:
1664:
1657:
1649:
1643:
1639:
1638:
1630:
1628:
1626:
1606:
1602:
1598:
1594:
1590:
1586:
1582:
1578:
1574:
1567:
1560:
1558:
1556:
1548:
1544:
1540:
1536:
1532:
1528:
1523:
1522:gr-qc/0109029
1518:
1514:
1510:
1503:
1501:
1499:
1497:
1482:
1478:
1471:
1456:
1454:9780786737000
1450:
1446:
1445:
1437:
1422:
1415:
1407:
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1397:
1390:
1382:
1381:
1373:
1365:
1363:9780198240112
1359:
1355:
1348:
1340:
1336:
1332:
1328:
1324:
1320:
1316:
1309:
1301:
1297:
1293:
1289:
1285:
1281:
1280:
1275:
1269:
1261:
1257:
1253:
1249:
1245:
1241:
1237:
1230:
1222:
1218:
1214:
1210:
1206:
1202:
1198:
1194:
1193:
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1177:
1175:9783319488622
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1167:
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1152:
1148:
1144:
1140:
1136:
1132:
1127:
1122:
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1114:
1107:
1099:
1097:9781567180855
1093:
1089:
1088:
1080:
1066:
1064:0-387-98571-9
1060:
1055:
1054:
1045:
1031:
1027:
1020:
1012:
1006:
1002:
995:
980:
976:
975:"Time Travel"
969:
967:
958:
956:1-56396-653-0
952:
948:
941:
933:
927:
923:
916:
908:
902:
898:
894:
887:
879:
877:1-4020-1200-4
873:
869:
865:
860:
859:gr-qc/0206078
855:
851:
844:
842:
840:
838:
822:
818:
817:"Time Travel"
811:
809:
807:
805:
803:
795:
789:
785:
781:
774:
772:
763:
757:
753:
749:
742:
740:
738:
736:
734:
725:
723:9780786478071
719:
715:
711:
704:
696:
692:
687:
686:gr-qc/0206078
682:
678:
674:
667:
659:
655:
648:
640:
638:9781439168486
634:
630:
626:
619:
617:
602:
598:
591:
587:
578:
575:
573:
570:
568:
565:
563:
560:
558:
555:
553:
550:
548:
545:
543:
540:
538:
535:
533:
530:
528:
527:Fermi paradox
525:
523:
520:
519:
513:
511:
506:
502:
501:David Deutsch
498:
496:
491:
481:
479:
478:event horizon
475:
470:
465:
463:
458:
453:
449:
445:
444:billiard ball
441:
436:
434:
430:
427:that contain
426:
422:
419:permits some
418:
414:
410:
404:
394:
391:
386:
382:
378:
374:
370:
366:
356:
353:
344:
342:
338:
334:
327:Illusory time
324:
322:
321:Norman Swartz
318:
314:
310:
305:
303:
299:
294:
279:
277:
273:
268:
264:
260:
256:
250:
240:
237:
235:
231:
230:the Holocaust
227:
223:
219:
218:
206:
204:
200:
196:
192:
188:
177:
168:
160:
158:
154:
153:
147:
146:
141:
136:
134:
130:
126:
122:
118:
108:
106:
102:
98:
94:
90:
86:
85:bootstrapping
78:
74:
69:
62:
60:
59:time dilation
56:
52:
48:
44:
40:
33:
19:
2446:Misner space
2431:Gödel metric
2411:can contain
2300:
2145:
2141:
2135:
2092:
2088:
2082:
2049:
2045:
2036:
2026:February 25,
2024:. Retrieved
2020:the original
2009:
1998:, retrieved
1994:
1984:
1941:
1937:
1931:
1912:
1906:
1887:
1845:
1841:
1831:
1811:
1769:
1765:
1755:
1716:(15): 4109,
1713:
1709:
1703:
1670:
1666:
1656:
1636:
1612:. Retrieved
1605:the original
1576:
1572:
1515:(6): 06401,
1512:
1509:Phys. Rev. D
1508:
1484:. Retrieved
1480:
1470:
1460:December 18,
1458:. Retrieved
1443:
1436:
1425:. Retrieved
1414:
1395:
1389:
1379:
1372:
1353:
1347:
1322:
1318:
1308:
1283:
1277:
1268:
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1239:
1229:
1196:
1190:
1184:
1165:
1159:
1116:
1112:
1106:
1086:
1079:
1068:. Retrieved
1052:
1044:
1033:, retrieved
1029:
1019:
1000:
994:
982:. Retrieved
978:
946:
940:
921:
915:
892:
886:
849:
824:. Retrieved
820:
779:
747:
709:
703:
676:
672:
666:
658:the original
647:
624:
604:, retrieved
600:
590:
499:
487:
468:
466:
437:
406:
389:
372:
368:
365:Igor Novikov
362:
350:
333:Gödel metric
330:
312:
306:
301:
297:
290:
276:supernatural
252:
238:
233:
226:World War II
222:Adolf Hitler
215:
212:
198:
194:
193:happen, but
190:
186:
183:
166:
150:
143:
137:
124:
120:
116:
114:
81:
68:
46:
43:time paradox
42:
38:
36:
2487:Time travel
2436:Kerr metric
2373:Determinism
2314:Causal loop
2220:Time travel
1614:16 November
1319:Philosophia
1240:Philosophia
984:November 2,
679:: 289–296.
577:Time travel
425:time travel
413:time travel
302:necessarily
293:modal logic
133:time travel
55:time travel
2476:Categories
2403:Spacetimes
2378:Eternalism
2345:Multiverse
2102:1912.02301
2095:(93): 93.
1486:2017-12-13
1427:2016-04-21
1405:0198236212
1070:2022-02-19
1010:0262580888
583:References
452:Kip Thorne
438:Physicist
341:block time
337:Kurt Gödel
304:happened.
2497:Causality
2388:Free will
2284:Time loop
2127:208637445
1601:250912686
1339:143485859
1260:143485859
567:Time loop
547:Causality
267:causality
140:spacetime
105:time loop
101:free will
77:time loop
2383:Fatalism
2180:18597824
2074:10013776
1870:10013968
1809:(1994).
1748:16517920
1695:10013039
1547:18460829
1423:. SFU.ca
1213:41931515
1192:Synthese
1151:51796022
826:June 13,
542:Wormhole
516:See also
448:wormhole
209:Variants
2289:in film
2160:Bibcode
2107:Bibcode
2054:Bibcode
2000:May 25,
1976:2869291
1956:Bibcode
1850:Bibcode
1774:Bibcode
1728:Bibcode
1675:Bibcode
1581:Bibcode
1527:Bibcode
1300:2027068
1131:Bibcode
1035:May 25,
864:Bibcode
752:136–139
691:Bibcode
606:May 25,
379:of the
199:did not
51:paradox
49:, is a
2178:
2125:
2072:
1974:
1919:
1894:
1868:
1819:
1746:
1693:
1644:
1599:
1545:
1451:
1402:
1360:
1337:
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1258:
1221:113227
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1172:
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1094:
1061:
1007:
953:
928:
903:
874:
790:
758:
720:
635:
469:ad hoc
390:closed
373:Jinnee
234:reason
195:cannot
2176:S2CID
2150:arXiv
2123:S2CID
2097:arXiv
1972:S2CID
1946:arXiv
1744:S2CID
1718:arXiv
1608:(PDF)
1597:S2CID
1569:(PDF)
1543:S2CID
1517:arXiv
1335:S2CID
1296:JSTOR
1256:S2CID
1217:S2CID
1209:JSTOR
1147:S2CID
1121:arXiv
854:arXiv
681:arXiv
629:60–62
381:Quran
123:, an
119:, an
65:Types
45:, or
2409:that
2070:PMID
2028:2012
2002:2019
1917:ISBN
1892:ISBN
1866:PMID
1817:ISBN
1691:PMID
1642:ISBN
1616:2015
1462:2017
1449:ISBN
1400:ISBN
1358:ISBN
1170:ISBN
1092:ISBN
1059:ISBN
1037:2019
1005:ISBN
986:2015
951:ISBN
926:ISBN
901:ISBN
872:ISBN
828:2015
788:ISBN
756:ISBN
718:ISBN
633:ISBN
608:2019
377:Jinn
369:Jinn
228:and
2405:in
2168:doi
2115:doi
2062:doi
1964:doi
1858:doi
1782:doi
1736:doi
1683:doi
1589:doi
1535:doi
1327:doi
1288:doi
1248:doi
1201:doi
1197:190
1139:doi
1117:245
784:581
298:is,
191:did
187:can
131:or
2478::
2174:.
2166:.
2158:.
2146:69
2144:.
2121:.
2113:.
2105:.
2093:51
2091:.
2068:.
2060:.
2050:44
2048:.
1993:,
1970:.
1962:.
1954:.
1942:55
1940:.
1878:^
1864:.
1856:.
1846:44
1844:.
1840:.
1796:^
1780:.
1770:21
1768:.
1764:.
1742:,
1734:,
1726:,
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1681:.
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1665:.
1624:^
1595:.
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1554:^
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1323:17
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1317:.
1294:.
1284:85
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