Roger Penrose's pre-big bang eon?

[Nelda]

Penrose's theory is not presently generally accepted by other physicists.
But that doesn't mean he isn't correct.
Logic dictates that if energy was released in the big bang, then it has to have come from somewhen / somewhere.
He is one of many mathematicians attempting to explain the origin of the universe.

As far as we know there is no antimatter in our universe.
If there was some at some stage, I don't know. Penrose is very likely to know this, or at least express an opinion.
If antimatter was able to be created once then why wouldn't it be created at a future big bang event.
It seems a moot point.
Nothing of this universe would survive the transition to the next (if there is a next one).

 

[erockin]

Again, I'm not a physicist, and help would be appreciated. With Roger Penrose's recent exclamations about evidence of a pre-big bang eon, a few questions have arisen for me. I have extrapolated (very likely incorrectly) that Mr. Penrose (I assume doctor is the proper term, but I cannot recall hearing it) is alluding to some sort of steady state theory. I can only gather from what I have read that his calculations are referring to some sort of consistent reproducing big bang cycle (which may be wrong).

But, my ultimate question/confusion on the subject is... if our current understanding of the universe/big bang theory is that there was (for no understood reason) slightly more matter than antimatter in the birthing stages of the universe, and inevitably antimatter lost out to matter. Than where does all the antimatter come from in the next eon? I feel I may have to elaborate further, but hopefully I was clear enough for someone to understand my question.

 

[Betelgeuse]

Penrose's idea of a cyclical universe is not the same as a steady state one. In the Steady State theory, matter is constantly being created in empty space as it expands, resulting in a universe with a constant entropy state. It's an outdated theory because it doesn't explain why matter is clumped into galaxies or the existence of quasars.

A cyclical universe will eventually collapse on itself re expand again. Penrose claims there are patterns in the Cosmic Microwave Background that indicate black holes from the previous cycle colliding with the homogeneous background soup of the new one. He also doesn't believe there was an inflationary period, which has little evidence to support it anyway.

It has been shown that there is asymmetry between matter and anti-matter having to do with their weak nuclear interactions. So as matter and anti-mattter annihilate each other, a small remnant of matter is left over, which explains why there is matter in the universe but little or no anti-matter. This would produce a huge amount of radiation in the universe as opposed to matter, but that also fits observation. By this time, however, it has spread out even into the huge voids between galaxy clusters, while matter tends to clump together.

 

[PaulH]

Sir Roger Penrose proposes that the universe is a result of cyclical events and that the forces of nature somehow evolved....how he determined that, I don't know. I'm not sure how he proposes the resupply of anti-matter either...or if it's even necessary according to his model. This article may explain it better...
http://www.bbc.co.uk/news/science-environment-11837869

"Evidence of events that happened before the Big Bang can be seen in the glow of microwave radiation that fills the Universe, scientists have asserted.

Renowned cosmologist Roger Penrose said that analysis of this cosmic microwave background showed echoes of previous Big Bang-like events.

The events appear as "rings" around galaxy clusters in which the variation in the background is unusually low."

I haven't read his entire proposals so I can't say how he concludes that the "rings" which he found explain his model and oppose Big Bang cosmology or how the forces of nature could have evolved multiple times. There are also observations of "intergalactic shadows" which seem to indicate a problem with the CMB as being a proposed "echo" of the Big Bang event.

"Big Bang's Afterglow Fails Intergalactic 'Shadow' Test
ScienceDaily (Sep. 5, 2006) — The apparent absence of shadows where shadows were expected to be is raising new questions about the faint glow of microwave radiation once hailed as proof that the universe was created by a "Big Bang."

http://www.sciencedaily.com/releases/2006/09/060905104549.htm

Another article explains that the rings are supposedly a normal expectation of CMB.......

"Mainstream cosmologists, who have seen a long list of anomalies in the cosmic background come and go, were not impressed. Now their skepticism is supported by two groups of cosmologists, Ingunn Kathrine Wehus and Hans Eriksen of the University of Oslo in Norway and Adam Moss, Douglas Scott and James P. Zibrin, all of the University of British Columbia. In separate papers based on data from the Wilkinson satellite, both groups reported finding such rings, but said the rings were consistent with having arisen by chance in the earliest moments of our own universe. Eternity is not needed to explain them.

Dr. Moss and his colleagues wrote, “Gurzadyan and Penrose have not found evidence for pre-Big Bang phenomena, but have simply rediscovered that the CMB contains structure.”

http://www.nytimes.com/2010/12/14/science/space/14cosmic.html

And there are also proponents of a theory for the universe called "plasma cosmology" ...that many of the observations in the universe are better explained by plasma and electromagnetic phenomena. It also negates the need for hypothetical dark matter and energy.

http://jvr.freewebpage.org/TableOfContents/Volume3/Issue3/APlasmaUniverse.pdf

http://www.youtube.com/watch?v=wOI-X215A8Y

http://www.youtube.com/watch?v=zFEVM-IkXLA&feature=related

http://www.youtube.com/watch?v=tIbUK3c9zak&NR=1

 

[Taimoor]

I am not entirely sure on this one but I think the current understanding is this:

Pure energy can be converted to matter as E=mc^2 (Yes, I know everyone knows this but important to confirm nonetheless). However, energy can not just be converted to matter due to various conservation laws. Hence, it is only possible to create matter-antimatter pairs (http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970724a.html). If in the pre-big bang eon there was a big crunch and all the matter was converted to energy, this energy can conceivably be reconverted in to matter/antimatter pairs.

However, there is a problem with this. If the change happened like this, it will be very difficult to explain why there were different amount of matter and antimatter in the first place. Since, this is not explained using existing theories also, this should not be a handicap to Penrose's theory. Honestly speaking, without an understanding of quantum gravity, these questions are very hard to answer.