So Long Big Bang, Hello Big Bounce

A scientific paper was released yesterday in the online version of the journal Nature Physics that may provide answers not only to the origin of our Universe, but may describe some conditions of what was there before.

Martin Bojowald, assistant professor of physics at Penn State has found a way to combine some calculations of quantum physics, which is very good at describing very extreme units of energy and mass, with classical physics, which is better at describing things like orbits and gravity. Physicists have been trying for nearly a century to reconcile the two types into a unified theory that would cast a better light, as it were, into how the Universe works.

When Albert Einstein was working on the problem of the Universe's origin, his calculations showed that the Big Bang resulted from a "singularity" of infinite mass and energy with zero volume. This would have meant that all the planets and stars originated from nothing. While that might be a satisfying answer for poets and preachers, it's not been at all satisfying for science.

Bojowald's theory, called Loop Quantum Gravity, is able to describe a condition of Universal start that has a mass and energy less than infinite and a volume greater than zero. The Big Bang, then, becomes the Big Bounce where our Universe was born out of the contraction of another Universe with a similar space-time geometry.

According to Quantum Gravity, a theory upon which Bojowald's theory was built, the Universe is comprised at the sub-atomic level of one-dimensional quantum threads. Under the extreme energy conditions of the Big Bounce, these threads react in a way that throws gravity into reverse--instead of attracting, it repels.

Loop Quantum Gravity theory uses sets of equations to figure things out going backwards in time through the bounce and further still into the previous condition. One very interesting indication of this theory is that the previous Universe is not likely to be a copy of our own. According to the Penn State Web site:

The model's equations also contain some "free" parameters that are not yet known precisely but are nevertheless necessary to describe certain properties. Bojowald discovered that two of these free parameters are complementary: one is relevant almost exclusively after the Big Bounce and the other is relevant almost exclusively before the Big Bounce. Because one of these free parameters has essentially no influence on calculations of our current universe, Bojowald colludes that it cannot be used as a tool for back-calculating its value in the earlier universe before the Big Bounce.

Also, Bojowald found that at least one of the parameters used to describe the previous state was useless in describing this one. This leads him to conclude, "the eternal recurrence of absolutely identical universes would seem to be prevented by the apparent existence of an intrinsic cosmic forgetfulness."