from The American Heritage® Dictionary of the English Language, 5th Edition.

  • adjective Of or relating to a cosmological theory proposing that the known universe originated in the collision of two other three-dimensional universes traveling in a hidden fourth dimension. This scenario does not require a singularity at the moment of the Big Bang.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • adjective Used in the names "ekpyrotic universe" or "ekpyrotic scenario", coined specifically to name this theory.
  • adjective Relating to the ekpyrotic scenario, e.g. ekpyrotic cosmology.


from The American Heritage® Dictionary of the English Language, 4th Edition

[Greek ekpurōsis, conflagration, cyclically recurring conflagration in which the universe is destroyed and reborn according to Stoic philosophy (from ex, ek, out of; see eghs in Indo-European roots + pūr, pur-, fire; see paəwr̥ in Indo-European roots + -ōsis, n. suff.) + –otic.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

Coined in 2001 by Paul Steinhardt, from Ancient Greek εκπυρωσι&ς (ekpurōsis) "conflagration, ekpyrosis", referring in Stoic philosophy to the destruction and recreation of the world in fire.


  • Steinhardt is the author of the quintessence theory and a cosmological idea called ekpyrotic (if I remember the spelling).

    A Dark, Misleading Force

  • String theory offers mechanisms to get around the singularity problem of the big bang: Physicists Paul Steinhardt and Neil Turok have proposed an " ekpyrotic " model, where two universes floating in multidimensional space collide to produce a new beginning for the universe.

    How It

  • Both take advantage of branes and extra dimensions to try to follow cosmological evolution right through the purported Big Bang singularity; in the ekpyrotic case, there is a unique turnaround point, whereas in the cyclic case there are an infinite number of bounces stretching endlessly into the past and the future.

    How Did the Universe Start?

  • Any bounce or ekpyrotic model will not give us an answer to creation?

    Against Bounces

  • A related set of ideas have been advanced by Steinhardt, Turok, and collaborators, first as the ekpyrotic scenario and later as the cyclic universe scenario.

    How Did the Universe Start?

  • One might also count more specific cosmic scenarios like DBI inflation, pre-Big-Bang cosmology, the ekpyrotic universe, and brane gas cosmologies.

    Guest Blogger: Joe Polchinski on the String Debates

  • There remains room for alternatives like the ekpyrotic cyclic universe model of Steinhart and Turock (see _Analog_, April 2002 and January 2003), in which two extra-dimensional "branes" clap together to produce a later-stage Big Bang with no inflation or initial singularity.

    Analog Science Fiction and Fact

  • The real target for this assertion is the ekpyrotic universe theory, something with which Hawking disagrees.

    The Full Feed from

  • The ekpyrotic universe model, suggested by Paul Steinhardt and Neil Turok, tells a similar story.

    New Scientist - Online News

  • In ekpyrotic cosmology our Universe was formed by similar collision of many branes, but in substantially larger scope, then the LHC could provide. - latest science and technology news stories


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