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properties. Instead of making clear predictions, the Big Bang inflationary theory allows any outcome, so that the properties we observe may be viewed as random chance, resulting from the particular patch of the multiverse in which the Earth resides. Most regions of the multiverse would have very different properties.
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are properly included in the Big Bang inflationary model, they prevent the universe from achieving the uniformity and flatness that the cosmologists are trying to explain. Instead, inflated quantum fluctuations cause the universe to break up into patches with every conceivable combination of physical
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inflationary model, "What happened before the Big Bang?" The explanation, according to the ekpyrotic theory, is that the Big Bang was actually a big bounce, a transition from a previous epoch of contraction to the present epoch of expansion. The key events that shaped our universe occurred before the
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In ekpyrotic and cyclic models, smoothing and flattening occurs during a period of slow contraction, so quantum fluctuations are not inflated and cannot produce a multiverse. As a result, the ekpyrotic and cyclic models predict simple physical properties that are consistent with current experimental
345:
Nobel laureate Steven
Weinberg has suggested that if the multiverse is true, “the hope of finding a rational explanation for the precise values of quark masses and other constants of the standard model that we observe in our Big Bang is doomed, for their values would be an accident of the particular
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experiments. Observation of a CMB has long been considered evidence of the Big Bang, but proponents of the ekpyrotic and cyclic theories contend that the CMB is also consistent with a Big Bounce as posited in those models. Other researchers argue that data from the Planck observations of the CMB
252:, but most contemporary ekpyrotic and cyclic models use the same physical ingredients as inflationary models (quantum fields evolving in ordinary space-time). Like Big Bang cosmology, the ekpyrotic theory has accurately described essential features of our universe. It predicts a
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The idea that the properties of our universe are an accident and come from a theory that allows a multiverse of other possibilities is hard to reconcile with the fact that the universe is extraordinarily simple (uniform and flat) on large scales and that elementary
695:
Juvela, M.; Jones, W. C.; Jaffe, T. R.; Jaffe, A. H.; Huffenberger, K. M.; Hovest, W.; Hornstrup, A.; Holmes, W. A.; Hobson, M. (2014). "Planck 2013 Results. XXIV. Constraints on primordial non-Gaussianity".
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appear to be described by simple symmetries and interactions. Also, the accidental concept cannot be falsified by an experiment since any future experiments can be viewed as yet other accidental aspects.
423:
Khoury, Justin; Ovrut, Burt A.; Steinhardt, Paul J.; Turok, Neil (2001). "The
Ekpyrotic Universe: Colliding Branes and the Origin of the Hot Big Bang".
479:, all-engulfing cosmic fire, represents the contractive phase of eternally-recurring destruction and re-creation. On "ekpyrosis" see generally
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Ovrut, Burt A.; Khoury, Justin; Buchbinder, Evgeny I. (2008). "Non-Gaussianities in New
Ekpyrotic Cosmology".
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cosmological model in which the universe is caught in an eternal cycle of fiery birth, cooling and rebirth.
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Veneziano, G. (1998-02-09). "A Simple/Short
Introduction to Pre-Big-Bang Physics/Cosmology".
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The
Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory
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theory), which proposes a complete cosmological history, both the past and future.
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with patterns of hot spots and cold spots, in agreement with observations of the
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Marfatia, Danny; Lee, Hye-Sung; Barger, V. (2003-02-18). "WMAP and
Inflation".
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Steinhardt, P. J.; Turok, N. (2002-04-25). "A Cyclic Model of the
Universe".
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bounce, and, in a cyclic version, the universe bounces at regular intervals.
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The theory addresses the fundamental question that remains unanswered by the
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Kallosh, Renata; Kofman, Lev; Linde, Andrei (2001). "Pyrotechnic universe".
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An advantage of ekpyrotic and cyclic models is that they do not produce a
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by
Steinhardt, Paul J., Department of Physics, Princeton University.
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475:'The dissolution of the universe into fire'. In Stoic philosophy,
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The original ekpyrotic model was introduced by Justin Khoury,
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that explains the origin of the large-scale structure of the
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264:(CMB), observations confirmed to higher precision by the
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871:(the first paper to point out problems with the theory).
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904:Yi-Fu Cai, Damien A. Easson, Robert Brandenberger,
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49:. Unsourced material may be challenged and removed.
893:Parallel Universes, (BBC Two, 9 February 14, 2002)
899:'Brane-Storm' Challenges Part of Big Bang Theory
337:. This is important because when the effects of
220:(ἐκπύρωσις, "conflagration"), which refers to a
487:Cambridge University Press, 1978, pp. 161–186 .
797:A Brief Introduction to the Ekpyrotic Universe
181:. The model has also been incorporated in the
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359:evidence without producing a multiverse.
212:Steinhardt created the name based on the
109:Learn how and when to remove this message
906:Towards a Nonsingular Bouncing Cosmology
240:The original ekpyrotic models relied on
776:Paul J. Steinhardt; Neil Turok (2007).
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749:Weinberg, Steven (November 20, 2007).
483:, "Stoic Cosmology", in John M. Rist,
815:, Vintage (2000), ISBN 9780099289920.
779:Endless Universe: Beyond the Big Bang
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751:"Physics: What we do and don't know"
47:adding citations to reliable sources
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908:, arXiv:1206.2382, (June 2012).
34:needs additional citations for
666:10.1103/PhysRevLett.100.171302
275:Primordial gravitational waves
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592:10.1016/S0370-2693(03)00757-3
755:The New York Review of Books
698:Astronomy & Astrophysics
403:American Heritage Dictionary
312:or discuss the issue on the
728:10.1051/0004-6361/201321554
262:cosmic microwave background
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851:10.1103/PhysRevD.64.123523
455:10.1103/PhysRevD.64.123522
304:towards certain viewpoints
281:Implications for cosmology
236:Applications of the theory
187:ekpyrotic cyclic universe
720:2014A&A...571A..24P
636:Physical Review Letters
531:10.1126/science.1070462
922:Astrophysics concepts
882:News. April 10, 2001.
889:February 2004 issue.
874:Whitehouse, David, "
385:Notes and references
339:quantum fluctuations
58:"Ekpyrotic universe"
43:improve this article
887:Before the Big Bang
885:Discover Magazine,
876:Before the Big Bang
843:2001PhRvD..64l3523K
658:2008PhRvL.100q1302B
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485:The Stoics,
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399:"ekpyrotic"
322:August 2019
185:theory (or
916:Categories
335:multiverse
302:unbalanced
207:Neil Turok
199:Burt Ovrut
69:newspapers
859:0556-2821
782:. Crown.
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568:: 33–41.
477:ekpyrosis
352:particles
314:talk page
218:ekpyrosis
209:in 2001.
99:June 2019
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363:See also
229:Big Bang
175:universe
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704:: A24.
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266:WMAP
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