In theoretical cosmology, the term ekpyrotic cosmology (Khoury-Ovrut-Steinhardt-Turok 01) refers to the hypothesis that the observable universe is the locus of the collision of two branes in an ambient higher-dimensional spacetime. The scenario is vaguely motivated from the Randall-Sundrum model (which in turn was vaguely motivated from Horava-Witten theory) but with the two branes there not being static but colliding with or even passing through each other, possibly repeatedly (“cyclic cosmology” Steinhardt-Turok 01).
Just like the Randall-Sundrum model, also the ekpyrotic model is loosely string theory inspired but initially without the ambition to check whether there really are string theory vacua with these proporties. Recent more detailed analysis points to the contrary (Uzawa 18).
The idea was proposed in
Justin Khoury, Burt Ovrut, Paul Steinhardt, Neil Turok, The Ekpyrotic Universe: Colliding Branes and the Origin of the Hot Big Bang, Phys. Rev. D64:123522,2001 (arXiv:hep-th/0103239)
Paul Steinhardt, Neil Turok, Cosmic Evolution in a Cyclic Universe, Phys. Rev. D65:126003, 2002 (arXiv:hep-th/0111098)
Justin Khoury, Burt Ovrut, Paul Steinhardt, Neil Turok, Density Perturbations in the Ekpyrotic Scenario, Phys. Rev. D66:046005, 2002 (arXiv:hep-th/0109050)
Evgeny Buchbinder, Justin Khoury, Burt Ovrut, New Ekpyrotic Cosmology, Phys. Rev. D76:123503, 2007 (arXiv:hep-th/0702154)
See also
Discussion of no-go theorems for actually embedding the ekpyrotic scenario in string theory, or at least in type IIA supergravity:
Kunihito Uzawa, No-Go theorems for ekpyrosis from ten-dimensional supergravity, J. High Energ. Phys. (2018) 2018: 41 (arXiv:1803.11084, doi:10.1007/JHEP06(2018)041)
reviewed in:
Kunihito Uzawa, Ekpyrotic scenario in string theory (pdf)
This is related to similar discussion of embedding de Sitter vacua into string theory, see the references there.
Last revised on April 10, 2020 at 11:40:46. See the history of this page for a list of all contributions to it.