Matter creation, dark energy, and the possibility of a Big Crunch

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Hi physicsforum members,
I am currently in a discussion with a fellow traveler on the chances of a Big Crunch. To my knowledge, it's a long shot. But to him it is the accepted mainstream view on the "ends" of the universe.
Before I get to my question, I have to provide some back story (I will be quoting from his hypotheses and proofs):
Hypothesis: Dark Energy is being converted to Dark Matter at one of three rates.
Fact: At the moment of the Big Bang, there was no Dark Matter.
Fact: At the moment of the Big Bang, there was at least 96% Dark Energy.
Fact: At 13.73 billion years, the Universe is 73% Dark Energy, 23% Dark Matter, and 4% Ordinary Matter.
He seems to think this other 73% of dark energy will cool (although now he has moved away from "cooling" but still thinks this dark energy will convert into matter causing a big crunch. I told him this is a correlation/causation fallacy, but he just won't give it up.
The universe, by Hawking's model which answers all the contradictions, is boundless yet finite. And it does have a very nice center, the near-infinite singularity
This is another conclusion of his, that he says was confirmed by the WMAP. But from what I know, and my research on the WMAP, this is not the case.
Final Conclusion: All (or nearly all) of the Dark Energy will be converted into Dark Matter in between 26 and 82 billion years. Logic suggests 25.9, though observation suggests 45.6.
This is a further argument of his on the creation of matter from dark energy.

I'm just a lowly anthropolgy major, he a philosophy major, so I am looking for people who are more qualified to speak on the issue. Is he as massively mistaken (and bordering on crank-ism) as I think he is? If you can, please use citations and maths. This isn't necessary. But I want to have a firm grasp of the issue before I continue mine and his discussion.
 

Answers and Replies

mathman
Science Advisor
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Where did he get his "facts"? The first two, especially the second, look suspicious. The third is essentially correct.
 
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I'm just a lowly anthropolgy major, he a philosophy major, so I am looking for people who are more qualified to speak on the issue. Is he as massively mistaken (and bordering on crank-ism) as I think he is? If you can, please use citations and maths. This isn't necessary. But I want to have a firm grasp of the issue before I continue mine and his discussion.
Just about everything you've mentioned so far is completely wrong.
A cursory reading of some of the following wikipedia articles is plenty to clear up the issues.
http://en.wikipedia.org/wiki/Dark_matter" [Broken]
http://en.wikipedia.org/wiki/Dark_energy" [Broken]
http://en.wikipedia.org/wiki/History_of_the_universe" [Broken]
http://en.wikipedia.org/wiki/Shape_of_the_universe" [Broken]

If you have specific questions feel free to ask them.
If your friend (like numerous 'philosophers' i know) is hell-bent on making up 'facts' to be wildly interpreted, instead of actually studying a subject in an attempt to learn something---then you shouldn't bother trying to convince him.
 
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Im looking for something specifically refuting his notion that dark energy is going to convert to matter. I mean, I have been looking for stuff, but it is, imo, so blatantly wrong as to be a non-issue. Nobody mentions anything along those lines... and in fact, from what I can tell, they say the opposite. It seems that dark energy is really the nail in the coffin for a Big Crunch, rather than evidence in favor of it.
Thanks for the answers so far. I told him that most of the matter in the universe was created in the first few moments of the Big Bang (which he took to mean seconds... could be but Im not sure) and that it cooled from a plasma/condensate, not from pure energy.
So my questions would be:
Will Dark Energy convert to matter?
What are the specifics of the "creation" of matter in the universe?
 
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Im looking for something specifically refuting his notion that dark energy is going to convert to matter.
Its not your job to refute something completely wrong and made-up.

first few moments of the Big Bang (which he took to mean seconds... could be but Im not sure)
Far, far smaller than seconds. See the timeline article I linked previously.

and that it cooled from a plasma/condensate, not from pure energy.
"Pure energy" doesn't really mean anything. We don't really know where the matter 'came from', but it is now---and presumably always was---some form of energy.

Will Dark Energy convert to matter?
Not to our knowledge. There is no reason (to my knowledge) to think this may be the case.

What are the specifics of the "creation" of matter in the universe?
You'll need to be a little more specific.
Some amount of matter was created, along with some amount of photons and dark matter.
Our present understanding suggests that dark energy might not have been created in the same way---but is instead a property of space itself. As the universe expands, so does the total 'amount' of dark energy (while the total amount of dark matter stays the same).
 
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Far, far smaller than seconds. See the timeline article I linked previously.
Ok. So am I correct in saying that most/all the matter in the universe was "created" between the Hadron Epoch and the Photon Epoch?

Some amount of matter was created, along with some amount of photons and dark matter.
Our present understanding suggests that dark energy might not have been created in the same way---but is instead a property of space itself. As the universe expands, so does the total 'amount' of dark energy (while the total amount of dark matter stays the same).
This is what I was thinking too. Am I correct in saying the data suggests Dark Energy is just the energy of the vacuum?
 
Nabeshin
Science Advisor
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This is what I was thinking too. Am I correct in saying the data suggests Dark Energy is just the energy of the vacuum?
This is a popular interpretation, yes, but I wouldn't say that the data suggests it. If we use our understanding of the vacuum from Quantum Field Theory and calculate what we might expect this "energy of the vacuum" to be, we get an answer 10^120 larger than what we observe. So it's actually in stark contrast with the data, but nonetheless remains a common interpretation.
 

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