From: helbig@asclothestro.multivax.de
In article ,
Lawrence Crowell writes:
>>>> QUOTE
>>>> However, they require that we are in the
>>>> centre of a large overdense region, which seems improbable on other
>>>> grounds.
>>>> END QUOTE
>>>>
>>>> This is an interesting point. A counter argument came to mind. If one
>>>> were to wager, bet, where they are in the universe then guessing one is
>>>> from the denser part of the universe would increase the odds of winning
>>>> the wager.
>>>
>>> Not "overdense"!
>>>
>>> Actually PH, like LC, appears to have misread the paper, or...
>>> Here is a quotation from the conclusions:
>>
>> No, you have misunderstood John's COUNTERargument, namely that---all
>> else being equal---one is more likely to be in an overdense region of
>> the universe than in an underdense one, simply because there is more
>> matter---and thus, presumably, more life---in overdense regions.
> To take this further, if the universe consisted of this local clump of
> matter, say in effect the universe consists in a coarse grained sense a
> central gravitating mass, then this would violate the observation the
> universe is homogeneous. The homogeneous universe at large then has a
> constant Ricci curvature or nabla R = 0, which is a feature of
> cosmological spacetimes.
The universe appears to be approximately homogeneous on large enough
scales. Of course a single clump would violate this, but no-one is
proposing a single clump, nor a completely empty bubble. Rather, the
question is whether it is possible that inhomogeneities---within the
current observational constraints---can have observable effects and
perhaps explain some puzzling observations (though it is fair to say
that not all are puzzled by them).
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* Origin: you cannot sedate... all the things you hate (1:229/2)
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