Cosmology

It's perhaps the biggest, most controversial mystery in the cosmos. Did our Universe just come into being by random chance, or was it created by a God who nurtures and sustains all life? The latest science is showing that the four forces governing our universe are phenomenally finely tuned. So finely that it had led many to the conclusion that someone, or something, must have calibrated them; a belief further backed up by evidence that everything in our universe may emanate from one extraordinarily elegant and beautiful design known as the E8 Lie Group. While skeptics hold that these findings are neither conclusive nor evidence of a divine creator, some cutting edge physicists are already positing who this God is: an alien gamester who's created our world as the ultimate SIM game for his own amusement. It's an answer as compelling as it is disconcerting.

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!)

Not to mention the question of which way it goes... Visit Discover Magazine to read this article and other exclusive science and technology news stories.

There is a strange and mysterious world that surrounds us, a world largely hidden from our senses.The quest to explain the true nature of reality is one of the great scientific detective stories.Clues have been pieced together from deep within the atom, from the event horizon of black holes, and from the far reaches of the cosmos.It may be that that we are part of a cosmic hologram, projected from the edge of the universe. Or that we exist in an infinity of parallel worlds. Your reality may never look quite the same again.

Physicist Brian Greene was propelled into the spotlight thanks to The Elegant Universe, his bestseller on string theory. Now he's turned his attention to parallel worlds. He tells Amanda Gefter about his favourite multiverse, why we might be living in a computer simulation and the questions that keep him awake at night

At Serious Play 2008, astrophysicist George Smoot shows stunning new images from deep-space surveys, and prods us to ponder how the cosmos -- with its giant webs of dark matter and mysterious gaping voids -- got built this way.

ScienceDaily (Mar. 20, 2011) - Physicists at UCLA set out to design a better transistor and ended up discovering a new way to think about the structure of space.

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.

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

May 4, 2011: Einstein was right again. There is a space-time vortex around Earth, and its shape precisely matches the predictions of Einstein's theory of gravity.Researchers confirmed these points at a press conference today at NASA headquarters where they announced the long-awaited results of Gravity Probe B (GP-B)."The space-time around Earth appears to be distorted just as general relativity predicts," says Stanford University physicist Francis Everitt, principal investigator of the Gravity Probe B mission.

Albert Einstein's towering reputation is only enhanced by his self-styled biggest blunder. It might not have been a blunder after all. At stake is the fate of the universe. In 1915, Einstein derived the equations of general relativity that describe the workings of a gravity-dominated cosmos. He added a fudge factor called the cosmological constant to ensure that, in keeping with contemporary tastes, the universe described neither expanded nor contracted. Soon after, though, Edwin Hubble showed that distant galaxies were receding from us, blowing the static universe apart. Einstein reputedly disowned his idea. He might now want to disown the disowning. The discovery in 1998 that very distant supernovae appear to be not just receding but accelerating away from us suggests the presence of a mysterious "dark energy" that counteracts gravity's pull (The Astronomical Journal, vol 116, p 1009). And it turns out that a good way to reproduce this effect is to add the fudge back into Einstein's cosmological recipe. That is not to everyone's taste, largely because no one knows what dark energy might be. Some cosmologists favour other solutions. If Earth were at the heart of a giant cosmic void, for instance, that too would create the illusion that the distant cosmos is flying away from us. But that would involve abandoning an idea we have held dear for centuries: the "Copernican principle" which says that Earth's place in the universe is not at all special (New Scientist, 15 November 2008, p 32). Working out the true story may take some time. But if the evidence collected on these pages is anything to go by, science rarely shies away from slaughtering its sacred cows.

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.

A theory of reality beyond Einstein's universe is taking shape - and a mysterious cosmic signal could soon fill in the blanks

Ptolemy's view that the stars are fixed points in the sky and our earth lay at the center of the known universe seemed to verify Aristotle's notion of the universe. We sure thought a lot of ourselves, but it stood to reason at the time.  We couldn't really see too far out from our home.  But the view was so appealing that even the gathering anomalies would not dissuade believers for nearly 1500 years.  On one level, it's comical to consider that humans thought of things in this way, but it is clearly scientifically stout compared to the Genesis account of the firmament.

(PhysOrg.com) -- Through precise cosmological measurements, scientists know that about 4.6% of the energy of the Universe is made of baryonic matter (normal atoms), about 23% is made of dark matter, and the remaining 72% or so is dark energy. Scientists also know that almost all the baryonic matter in the observable Universe is matter (with a positive baryon charge) rather than antimatter (with a negative baryon charge). But exactly why this matter and energy came to be this way is still an open question. In a recent study, physicists have proposed a new mechanism that can generate both the baryon asymmetry and the dark matter density of the Universe simultaneously.

ScienceDaily (Dec. 3, 2010) - Researchers from the Institute for Corpuscular Physics (IFIC) and other European groups have studied the effects of the presence of dark matter in the Sun. According to their calculations, low mass dark matter particles could be transferring energy from the core to the external parts of the Sun, which would affect the quantity of neutrinos that reach Earth.

A small change to the theory of gravity implies that our universe inherited its arrow of time from the black hole in which it was born.

Claims that there is something wrong with our standard model of the universe rest on flawed logic, say Andrew Pontzen and Hiranya Peiris

Physicists struggling to reconcile gravity with quantum mechanics have hailed a theory - inspired by pencil lead - that could make it all very simple

newscientist.com - A shape-shifting fifth fundamental force could neatly explain the mystery of dark energy and some other puzzling astronomical observations