The evidence that the universe emerged 14 billion years ago from an event called ‘the big bang’ is overwhelming. Yet the cause of this event remains deeply mysterious. In the conventional picture, the ‘initial singularity’ is unexplained. It is simply assumed that the universe somehow sprang into existence full of ‘inflationary’ energy, blowing up the universe into the large, smooth state we observe today. While this picture is in excellent agreement with current observations, it is both contrived and incomplete, leading us to suspect that it is not the final word. In this lecture, the standard inflationary picture will be contrasted with a new view of the initial singularity suggested by string and M-theory, in which the bang is a far more normal, albeit violent, event which occurred in a pre-existing universe. According to the new picture, a cyclical model of the universe becomes feasible in which one bang is followed by another, in a potentially endless series of cosmic cycles. The presentation will also review exciting recent theoretical developments and forthcoming observational tests which could distinguish between the rival inflationary and cyclical hypotheses.
Tagged with “einstein” (5)
Can you make your own universe? We usually think of the universe as “everything that exists,” so how could you make another one? Well, physicists have been speculating about the existence of multiple universes for some time now. And for Robert, the obvious next question was: “Can we make one?” So he invited physicist Brian Greene to his kitchen to speculate about just that. And it turns out, it’s not such a far-fetched idea. There are scientists right now trying to figure out whether it’s possible and what it would take. According to Brian, it would require a tiny black hole, a dash of reverse-gravity, and a lot of luck. But the laws of physics don’t rule it out.
Albert Einstein died more than half a century ago, but there’s still a raging debate over what he thought about religion. He once said "Science without religion is lame, religion without science is blind." In this hour of To the Best of Our Knowledge, what exactly did Einstein conclude about religion? We’ll hear from leading scientists and religious scholars, including Richard Dawkins, Steven Weinberg and Elaine Pagels, as well as Einstein biographer Walter Isaacson.
Steve Paulson speaks with Richard Dawkins, Elaine Pagels, and Einstein biographer Walter Isaacson. David Lindorff wrote about two physicists’ interest in mysticism and alchemy. David Leavitt tells the story of mathematician Srinivasa Ramanujan. Father Thomas Keating talks about God and the contemplative life.
Lawrence Krauss is a professor in the Department of Physics at Arizona State University. His lecture entitled Life, the Universe and Nothing was recorded at the Isabel Bader Theatre in Toronto on March 27th, 2009.
When writing the Principia Mathematica, Isaac Newton declared his hand on most of the big questions in physics. He outlined the nature of space, explained the motions of the planets and conceived the operation of gravity. He also laid down the law on time declaring:
“Absolute, true, and mathematical time, of itself and from its own nature, flows equably without relation to anything external.”
For Newton time was absolute and set apart from the universe, but with the theories of Albert Einstein time became more complicated; it could be squeezed and distorted and was different in different places.
Time is integral to our experience of things but we find it very difficult to think about. It may not even exist and yet seems written into the existence of absolutely everything.
Jim Al-Khalili, Professor of Theoretical Physics and Chair in the Public Engagement in Science at the University of Surrey
Monica Grady, Professor of Planetary and Space Sciences at the Open University
Ian Stewart, Professor of Mathematics at the University of Warwick
(sometimes, they pull these shows after a week…but there’s a real audio stream available on their site: http://www.bbc.co.uk/radio4/history/inourtime/rams/inourtime_20081218.ram)