The Universe is by definition everything that physically exists in space and time. It originated in the Big Bang 13.7 billion years ago. The radius of the Universe is at least 78 billion light years. That is the distance to the point from which a photon of light originated which is now reaching us after traveling for 13.7 billion years. However the Universe could be far larger. There is no limit to the speed at which space itself may expand, so the Universe may stretch far beyond the Hubble horizon expanding away from us faster than the speed of light. It is also conjectured that our Universe may be only one of 10500 other universes which may have totally different laws of nature and which are collectively called a multiverse.
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From the Carl Sagan's Pale Blue Dot. There are several different versions of "The Pale Blue Dot" on-line. The actual words were taken from Carl...
Is Our Universe at Home Within a Larger Universe?Last Updated on 2010-03-29 00:00:00BLOOMINGTON, Ind. (April 5, 2010) – Could our universe be located within the interior of a wormhole which itself is part of a black hole that lies within a much larger universe?
Such a scenario in which the universe is born from inside a wormhole (also called an Einstein-Rosen Bridge) is suggested in a paper from Indiana University theoretical physicist Nikodem Poplawski in Physics Letters B. The final version of the paper was available online March 29 and will be published in the journal edition April 12.
FIGURE CAPTION –– Einstein-Rosen bridges like the one visualized above have never been observed in nature, but they provide theoretical physicists and cosmologists with solutions in general relativity by combining models of black holes and white holes.
Poplawski takes advantage of the Euclidean-based coordinate system called isotropic coordinates to... More »
Astronomers: The end is nigher than we expectedLast Updated on 2010-01-27 00:00:00CANBERRA, AUSTRALIA (Jan. 26, 2010) – Cars run out of petrol, stars run out of fuel and galaxies collapse into black holes. As they do, the universe and everything in it is gradually running down. But how run down is it? Researchers from The Australian National University have found that the universe is 30 times more run down than previously thought.
PhD student Chas Egan and Dr Charley Lineweaver from the ANU Research School of Astronomy and Astrophysics have computed the entropy of the universe. Scientists compute entropy to figure out how efficient an engine is or how much work can be extracted from a fuel or how run down and disordered a system is. Using new data on the number and size of black holes they found that the universe contains 30 times more entropy than earlier estimates.
“We considered all contributions to the entropy of the observable universe: stars,... More »
Carl Sagan Discusses the 4th DimenionLast Updated on 2010-01-05 00:00:00Carl Sagan talks about the 4th dimension and how it is possible to understand curved space time as used by Einstein in his general theory of relativity. More »
'Our Place in the Cosmos'Last Updated on 2009-12-07 20:30:34
"Our Place in the Cosmos", the third video from the Symphony of Science, was crafted using samples from Carl Sagan's Cosmos, Richard Dawkins' Genius of Charles Darwin series, Dawkins' TED Talk, Stephen Hawking's Universe series, Michio Kaku's interview on Physics and aliens, plus added visuals from Baraka, Koyaanisqatsi, History Channel's Universe series, and IMAX Cosmic Voyage. The themes present in this song are intended to explore our understanding of our origins within the universe, and to challenge the commonplace notion that humans have a superior or privleged position, both on our home planet and in the universe itself.
RIP Dr. Sagan and Dr. Jastrow!
With every century
Our eyes on the universe have been opened anew
We are witness
To the very brink of time and space
We must ask... More »
'We Are All Connected'Last Updated on 2009-12-07 17:02:49
"We Are All Connected" was made from sampling Carl Sagan's Cosmos, The History Channel's Universe series, Richard Feynman's 1983 interviews, Neil deGrasse Tyson's cosmic sermon, and Bill Nye's Eyes of Nye Series, plus added visuals from The Elegant Universe (NOVA), Stephen Hawking's Universe, Cosmos, the Powers of 10, and more. It is a tribute to great minds of science, intended to spread scientific knowledge and philosophy through the medium of music.
We are all connected;
To each other, biologically
To the earth, chemically
To the rest of the universe atomically
I think nature's imagination
Is so much greater than man's
She's never going to let us relax
We live in an in-between universe
Where things change all right
But according to patterns, rules,
Or as we... More »
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