On 30-3-2010 18:11, Darren New wrote:
> andrel wrote:
>>> How about the fact that the stars of the universe are all red-shifted 
>>> the farther they get from *us*?  Or the fact that we seem to be the 
>>> only creatures in the entire *universe* that broadcast radio signals?
>>
>> For the latter see the Drake equation.
> 
> I'm familiar with it. What about it?

All we know that there are no radio signals broadcasted from a place 
exactly the right time ago to be just reaching us now, send towards us, 
and in a format that we recognize. Which is quite a long way away from a 
conclusion that no signals are send at all.

>>> People don't say "the red shift shows everything is moving away from 
>>> us" or "humans happen to live where time passes fastest in the 
>>> universe." They say "the red shift shows everything is moving away 
>>> from everything else."
>>
>> We say that because we believe in Lorentz invariance.
> 
> Yep. That doesn't mean things are moving away from us. We can't measure 
> whether they're moving away from us. All we can measure is the red 
> shift. The assumption is that the red shift is caused by relative 
> motion, and not the geometry of the universe.

I don't understand that last sentence, but that may be my physics 
background.

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