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Dark energy may not actually exist, scientists claim - Telegraph
Dark energy - the mysterious substance thought to make up three-quarters of the universe - may not actually exist, claims new research.
The concept of dark energy was created by cosmologists to fit Albert Einstein's General Theory of Relativity into reality after modern space telescopes discovered that the Universe was not behaving as it should.
According to Einstein's work, the speed at which the Universe is expanding following the Big Bang should be slower than it actually is and this unexplained anomaly threatened to turn the whole theory upside down. In order to reconcile this problem the concept of dark energy was invented.
But now Blake Temple and Joel Smoller, mathematicians at the University of California and the University of Michigan, believe they have come up with a whole new set of calculations that allow for all the sums to add up without the need for this controversial substance.
Dark Energy's Demise? New Theory Doesn't Use the Force
Dark energy, a mysterious force proposed more than a decade ago to explain why the universe is flying apart at an increasingly faster clip, is no longer necessary.
That's the conclusion of a controversial new theory that shows how the accelerated expansion of the universe could be just an illusion.
In a new study, two mathematicians present their solutions to Einstein's field equations of general relativity, which describe the relationship between gravity and matter.
Thinking About Time Before the Big Bang | Universe Today
What happened before the Big Bang? The conventional answer to that question is usually, "There is no such thing as 'before the Big Bang.'" That's the event that started it all. But the right answer, says physicist Sean Carroll, is, "We just don't know." Carroll, as well as many other physicists and cosmologists have begun to consider the possibility of time before the Big Bang, as well as alternative theories of how our universe came to be. Carroll discussed this type of "speculative research" during a talk at the American Astronomical Society Meeting last week in St. Louis, Missouri.
Hints of 'time before Big Bang' - BBC NEWS | Science/Nature
A team of physicists has claimed that our view of the early Universe may contain the signature of a time before the Big Bang.
The discovery comes from studying the cosmic microwave background (CMB), light emitted when the Universe was just 400,000 years old.
What Happened Before the Big Bang? : Paul Davies
Well, what did happen before the big bang?
Few schoolchildren have failed to frustrate their parents with questions of this sort. It often starts with puzzlement over whether space "goes on forever," or where humans came from, or how the planet Earth formed. In the end, the line of questioning always seems to get back to the ultimate origin of things: the big bang. "But what caused that?"
ASP: A Universe from Nothing
Insights from modern physics suggest that our wondrous universe may be the ultimate free lunch.
In the inflationary theory, matter, antimatter, and photons were produced by the energy of the false vacuum, which was released following the phase transition. All of these particles consist of positive energy. This energy, however, is exactly balanced by the negative gravitational energy of everything pulling on everything else. In other words, the total energy of the universe is zero! It is remarkable that the universe consists of essentially nothing, but (fortunately for us) in positive and negative parts. You can easily see that gravity is associated with negative energy: If you drop a ball from rest (defined to be a state of zero energy), it gains energy of motion (kinetic energy) as it falls. But this gain is exactly balanced by a larger negative gravitational energy as it comes closer to Earth’s center, so the sum of the two energies remains zero.
Big Bang - Wikipedia, the free encyclopedia
The Big Bang is a cosmological model of the initial conditions and subsequent development of the universe. It is supported by the most comprehensive and accurate explanations from current scientific evidence and observation.[1][2] As used by cosmologists, the term Big Bang generally refers to the idea that the universe has expanded from a primordial hot and dense initial condition at some finite time in the past, and continues to expand to this day.
Physical cosmology - Wikipedia, the free encyclopedia
Physical cosmology, as a branch of astronomy, is the study of the largest-scale structures and dynamics of our universe and is concerned with fundamental questions about its formation and evolution.[1] Cosmology involves itself with studying the motions of the celestial bodies and the first cause. For most of human history, it has been a branch of metaphysics and religion. Cosmology as a science originates with the Copernican principle, which implies that celestial bodies obey identical physical laws to those on earth, and Newtonian mechanics, which first allowed us to understand those motions. This is now called celestial mechanics. Physical cosmology, as it is now understood, began with the twentieth century development of Albert Einstein's general theory of relativity and better astronomical observations of extremely distant objects.
Richard Dawkins - Growing Up in the Universe - YouTube - Broadcast Yourself.
Five lectures by Oxford porfessor of biology Richard Dawkins
YouTube - Growing Up in the Universe - Richard Dawkins
Oxford professor Richard Dawkins presents a series of lectures on life, the universe, and our place in it. With brilliance and clarity, Dawkins unravels an educational gem that will mesmerize young and old alike. Illuminating demonstrations, wildlife, virtual reality, and special guests (including Douglas Adams) all combine to make this collection a timeless classic. The Royal Institution Christmas Lectures for Children were founded by Michael Faraday in 1825, with himself as the inaugural lecturer. The 1991 lecturer was Richard Dawkins whose five one-hour lectures, originally televised by the BBC, are now available free online, courtesy of The Richard Dawkins Foundation for Reason and Science. The entire 5-hour program is also available on a 2-DVD set through our online store. http://richarddawkins.net/store/index.php?main_page=product_info&products_id=5
13 things that do not make sense - space - 19 March 2005 - New Scientist Space
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