Tuesday, January 15, 2013

The immense Colossal Whizzbang Whangdangdoodle

Implications Of The Multiverse
On The Big Bang

or
How many theoretical physicists
specializing in general relativity
does it take to change a light bulb?
Two.
One to hold the bulb
and one to rotate the universe.


Hello friends!
I'm writing to you from an alternate universe in which time moves backwards, the planets orbit around Stephen Fry, The U.S. Congress is not comprised of racketeering imbeciles, & this article was never written. According to the Big Bang theory, our universe began extremely hot and extremely dense around 14 billion years ago. Space itself expanded and cooled down, eventually allowing atoms to form and clump together to build the stars and galaxies we see today. On this, most scientists are in agreement as there is plenty of evidence to indicate this is indeed so.
University of Pennsylvania particle physicist Burt Ovrut has said "I would say that there is 100 percent consensus, really, there is overwhelming evidence all of the predictions are true."
University Of Penn Physicist Burt Ovrut

For example, this theory predicted that the universe today would be filled with pervasive light left over from the Big Bang. This glow, called the cosmic microwave background radiation, was discovered in 1964,  20 years after it was predicted. However, what caused the Big Bang, what happened at that exact moment, and what came immediately after it, are much more open to contentious controversy, disputable debates, & general brouhaha.

Neil Turok
"Inflation is easily the most popular theory in cosmology," according to theoretical physicist Neil Turok, director of the Perimeter Institute for Theoretical Physics in Ontario, Canada. "It's a good theory, but it has some weak points. It can't describe the moment of the Big Bang."
The Big Bang theory envisions the universe beginning from a singularity, a mathematical concept of infinite temperature and infinite density packed into a single point of space. But scientists don't think this is what actually happened. "It wouldn't really be infinite," explained physicist Paul Steinhardt, director of the Princeton Center for Theoretical Science at Princeton University, who himself was one of the architects of the inflation theory. He noted "Infinity just means a mathematical breakdown. It's a statement that you shouldn't have extrapolated your equations back that far because they just blew up in your face."
So neither the Big Bang theory nor inflationary theory can describe what happened at that moment.

Princeton's Paul Steinhardt

There are some problems with inflation because of quantum fluctuations, different parts of the universe could inflate at different rates, creating "bubble universes" that are much larger than other regions. Our universe may be just one in a multiverse, where different scales and physical laws reign. In such a reality, everything and anything that can happen, will, so basically everything could be a prediction of inflation. This is a fundamental problem and we don't know how to escape it.
Of course there are scientists who say that while inflation may not be complete, it's still the most useful thing we've got to describe the origins of the universe.

Another case where the study of the smallest bits in the universe leads to an understanding of the largest bits is the idea of Cycles. The origins of which come from String Theory or "M Theory" more accurately  (a branch on the string theory tree).  Physicist Paul Steinhardt and Paul.Turok (Director of the Perimeter Institute for Theoretical Physics) proposed an idea called the cyclic model, based on an earlier concept called the ekpyrotic universe that they'd conceived with Ovrut.
In this scenario, the universe undergoes an endless sequence of "bangs" and "crunches".
 Periods of expansion followed by periods of contraction.
 At each transition, the universe would have some finite temperature and density, rather than the infinity of the singularity, and the expansion and contraction would be relatively slow, as opposed to the exponentially quick expansion proposed by inflation.

The idea is based on M-theory, a version of string theory which suggests that every particle is in fact a tiny loop of string whose vibration pattern determines what type of particle it will be. However, M-theory requires the universe to have 11 dimensions. So far, we can only detect four dimensions, three of space and one of time. The other seven are hidden, proponents say. Scientists call the four-dimensional part of the universe we can see a brane, (short for membrane) and suggest that other four-dimensional branes also exist inside this 11-dimesnional space.
"If you have another brane living in higher dimensions, it's extremely likely to move and slam into our own brane," Ovrut said. "You have a brane with exactly the structure of our real world, and other branes that are likely to hit us, and all of the energy of colliding universes would come into play. Gee, that sounds a heck of a lot like a Big Bang to me."
Advocates of the idea say it offers an exciting way of addressing the issue of what prompted the Big Bang, and it avoids some of the pitfalls of inflation such as infinity which is problematic.
Particles such as antimatter from a parallel universe, interacting with our own may be behind the mysterious deep space gamma bursts that have puzzled astronomers since their first observation.
"In the cyclic theory you are not only describing the last bang, but the ones before it," Turok explained. "It's a bigger picture, more complete and hopefully more logically consistent."
Schroedinger's Cat in it's natural habitat

The idea of alternate universes is not new, it's been around in Quantum Physics since the "many worlds" interpretation. In the Copenhagen interpretation, the mathematics of quantum mechanics allows one to predict probabilities for the occurrence of various events. In the many-worlds interpretation, all these events occur simultaneously.

What meaning should be given to these probability calculations?
And why do we observe, in our history, that the events with a higher computed probability seem to have occurred more often? One answer to these questions is to say that there is a probability measure on the space of all possible universes, where a possible universe is a complete path in the tree of branching universes. This is indeed what the calculations seem to give credence to. Of course this is all theory, yet quantum computing relies on a very real particle being in many places simultaneously, it relies on dimensions beyond the ones we perceive. Fortunately for those who work in this field, they don't particularly have to make sense of it or explain it, but rather just focus on the fact that it works. Indeed we are standing on a whale looking for minnows.






Sources-
  1. ^ Perimeter Institute, Seminar overview, Probability in the Everett interpretation: state of play, David Wallace - Oxford University, 21 Sept 2007
  2. ^ Perimeter Institute, Many worlds at 50 conference, September 21-24, 2007
  3. ^ Wojciech H. Zurek: Probabilities from entanglement, Born’s rule from envariance, Phys. Rev. A71, 052105 (2005).
  4. ^ M. Schlosshauer & A. Fine: On Zurek's derivation of the Born rule. Found. Phys. 35, 197-213 (2005).
  5. ^ Lutz Polley, Position eigenstates and the statistical axiom of quantum mechanics, contribution to conference Foundations of Probability and Physics, Vaxjo, Nov 27 - Dec 1, 2000
  6. ^ Lutz Polley, Quantum-mechanical probability from the symmetries of two-state systems
  7. ^ Armando V.D.B. Assis (2011). "Assis, Armando V.D.B. On the nature of and the emergence of the Born rule. Annalen der Physik, 2011.". Annalen der Physik (Berlin) 523: 883–897. arXiv:1009.1532. Bibcode 2011AnP...523..883A. doi:10.1002/andp.201100062.
  8. ^ Everett FAQ "Is many-worlds a local theory?"








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