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marcus
#10
Dec11-05, 12:42 PM
Astronomy
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Quote Quote by waderoo
I have a couple questions. The big bang happened and now the universe is expanding, and It will at some point contract and begin back at where and what it was at the big bang. Is that correct? ...
No, it is not correct, waderoo.
We are very far from knowing that this will happen.
There are several mathematical models that fit the data reasonably well and which people take seriously and NONE of them predicts a crunch AFAIK.

The simplest and most commonly used model, in cosmology, is called the "Lambda-CDM" model. It does NOT predict crunch. It is sometimes called "the consensus model" or words to that effect, because so many people accept it as the best fit so far.

So whoever told you crunch must have been misinformed or out of date.

AFAIK a new model could come along and predict crunch, but ever since about 1998 the accepted story is "Lambda-CDM" and it does not predict crunch.

Lambda essentially means "dark energy" and CDM means "cold dark matter"

So when you hear people talk about dark energy and dark matter they are usually talking about a model with no crunch.

the local experts like SpaceTiger---who is an insider with excellent qualifications---can confirm or correct this. it's true as far as I know