nLab ekpyrotic cosmology




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

See also

Embedding into string theory

Discussion of no-go theorems for actually embedding the ekpyrotic scenario in string theory, or at least in type IIA supergravity:

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 15:40:46. See the history of this page for a list of all contributions to it.