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Author Topic: Is infinity an illusion?  (Read 68522 times)

Offline dlorde

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Re: Is infinity an illusion?
« Reply #375 on: 06/11/2013 21:48:58 »
, if space was created at the big bang 15 billion years ago, it is 15 billion light years across. That's big but it's not infinite.
Seems to me that's true if only the universe expanded from a point (or, perhaps, it's only true of the observable universe). As I understand it, we don't know if the universe was a 'point source' at the big bang or not. It was extremely hot and extremely dense; but, for all we know, could have been infinitely large. But if it was larger than a point source, it could well be that most of it is outside our observable cosmic horizon.

I understand that the current cosmological proper distance (i.e. the comoving distance) for the diameter of the observable universe is actually about 93 billion light years (i.e. 46.5 bl from here to the observable 'edge').
 

Offline Bill S

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Re: Is infinity an illusion?
« Reply #376 on: 11/12/2013 18:17:42 »
Sorry to dig this one up again, but I would like to pick up on one of JP's points.

Quote from: JP
1a) Therefore, to answer whether there was ever "absolute nothing" we'd have to have a model that discriminates in terms of measurables between a scenario in which there was at one point "absolute nothing" and one in which there was not.

As you have pointed out elsewhere, "absolute nothing", if it can be said to exist, would be outside our Universe.  The only material we have from which to construct our model would be from within the Universe.  Would it not be impossible to construct a model that said anything about "absolute nothing"?
 

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Re: Is infinity an illusion?
« Reply #376 on: 11/12/2013 18:17:42 »

 

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