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They are the biggest questions that science can possibly ask: where did everything in our universe come from? How did it all begin? For nearly a hundred years, we thought we had the answer: a big bang some 14 billion years ago.But now some scientists believe that was not really the beginning. Our universe may have had a life before this violent moment of creation.Horizon takes the ultimate trip into the unknown, to explore a dizzying world of cosmic bounces, rips and multiple universes, and finds out what happened before the big bang.Neil Turok, Director of Perimeter Institute for Theoretical Physics in Canada, working with Paul Steinhardt at Princeton, has proposed a radical new answer to cosmology's deepest question: What banged?Answer: Instead of the universe inexplicably springing into existence from a mysterious initial singularity, the Big Bang was a collision between two universes like ours existing as parallel membranes floating in a higher-dimensional space that we're not aware of.One bang is followed by another, in a potentially endless series of cosmic cycles, each one spelling the end of a universe and the beginning of a new one. Not one bang, but many.Sir Roger Penrose has changed his mind about the Big Bang. He now imagines an eternal cycle of expanding universes where matter becomes energy and back again in the birth of new universes and so on and so on.

Space is festooned with vast "hyperclusters" of galaxies, a new cosmic map suggests. It could mean that gravity or dark energy - or perhaps something completely unknown - is behaving very strangely indeed. We know that the universe was smooth just after its birth. Measurements of the cosmic microwave background radiation (CMB), the light emitted 370,000 years after the big bang, reveal only very slight variations in density from place to place. Gravity then took hold and amplified these variations into today's galaxies and galaxy clusters, which in turn are arranged into big strings and knots called superclusters, with relatively empty voids in between. On even larger scales, though, cosmological models say that the expansion of the universe should trump the clumping effect of gravity. That means there should be very little structure on scales larger than a few hundred million light years across. But the universe, it seems, did not get the memo. Shaun Thomas of University College London (UCL), and colleagues have found aggregations of galaxies stretching for more than 3 billion light years. The hyperclusters are not very sharply defined, with only a couple of per cent variation in density from place to place, but even that density contrast is twice what theory predicts. "This is a challenging result for the standard cosmological models," says Francesco Sylos Labini of the University of Rome, Italy, who was not involved in the work.

"Has the cosmos existed forever, or did something bring it into existence? Time to grapple with the universe's greatest mystery"

"LONDON, Sep. 2, 2010 (Reuters) - God did not create the universe and the "Big Bang" was an inevitable consequence of the laws of physics, the eminent British theoretical physicist Stephen Hawking argues in a new book."

The Known Universe takes viewers from the Himalayas through our atmosphere and the inky black of space to the afterglow of the Big Bang. Every star, planet, and quasar seen in the film is possible because of the world's most complete four-dimensional map of the universe, the Digital Universe Atlas that is maintained and updated by astrophysicists at the American Museum of Natural History. The new film, created by the Museum,  is part of an exhibition, Visions of the Cosmos: From the Milky Ocean to an Evolving Universe, at the Rubin Museum of Art in Manhattan through May 2010.     Data: Digital Universe, American Museum of Natural History  http://www.haydenplanetarium.org/universe/    Visualization Software:  Uniview by SCISS    Director: Carter Emmart  Curator: Ben R. Oppenheimer  Producer: Michael Hoffman  Executive Producer: Ro Kinzler  Co-Executive Producer: Martin Brauen  Manager, Digital Universe Atlas: Brian Abbott    Music: Suke Cerulo    For more information visit http://www.amnh.org

Astronomers' new observations have spotted the most distant galaxy ever seen. The galaxy's light comes from about 13.1 billion light-years away, making it one of the first galaxies to form after the Big Bang.

TED Talks In Part 1 of his lecture at the University of Sydney, cosmologist Sean Carroll gives an entertaining and thought-provoking talk about the nature of time, the origin of entropy, and how what happened before the Big Bang might be responsible for the arrow of time we observe today. (Don't miss Part 2 of this talk!)

On October 11, 2010, Laura Mersini-Houghton appeared in a BBC programme What Happened Before the Big Bang (along with Michio Kaku, Neil Turok, Andrei Linde, Roger Penrose, Lee Smolin and other notable cosmologists and physicists) where she propounded her theory of the universe as a wave function on the landscape multiverse.[11] The programme referred to three observational tests of her theory's predictions, which makes it the only theory on the origins of our universe ever to offer predictions and have them successfully tested. Mersini-Houghton's work on multiverse theory is discussed in the epilogue of a recently published biography of Hugh Everett III.[12