Quote:
Originally Posted by SkyViking
But there won't be a 'last photon' will there?
The cosmological redshift will merely shift and dim the light until the point where we can no longer detect any signal from them, it will just get lost in the CMB eventually. And that will all happen for galaxy Y first.
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Thanks Rolf.
For this hypothetical example, I'm trying to ascertain whether or not there is a theoretical limit, so I've kind of assumed the CMB is out of the scope. I think this just makes it a bit less complicated .. (?)
So is what you say then, not just a practical detection issue ?
Ie: build a more powerful detector commensurate with the increase in redshifted wavelength/decrease in power ?
What I'm trying to ascertain is will the accelerated (metric) expansion of space mean that there will be an instant when both photons are simply not able to reach us - ie: we are causally disconnected ?
Cheers