[Nizzle (OP)]

Hi,

We're basing the fact that the universe is expanding mostly on the observed redshift of light from distant sources, but couldn't it be that this is an observational error, and that we actually live in a static universe (or a universe with a big bang but not accelerating expansion) where redshift is explained by some sort of "photon fatigue"?

A higher frequency indicates a more energetic photon, so if the photon would somehow lose some energy on it's way from the distant source to our optical instruments, it would be redshifted no?
And the accelerated expansion due to more redshift from more distant light sources could just be explained by the fact that the photon lost more energy because it traveled a longer distance?

Maybe the energy loss of the photon could be attributed to some sort of wave interference from the cosmic microwave background radiation?

[imatfaal]

Hi Nizzle

First objection would be observational; if you are correct then Andromeda galazy should be red-shifted as it is 2.6 Mlyr away.  However as it is gravitationally bound to us ou will find that it is actually blue-shifted

Second would be more theoretical; we already have a theory that work on known physics with no new interactions required - we need a good reason (ie  theory must explain more) to posit a new interaction

[Nizzle (OP)]

Andromeda's blue shift could be because it's doppler effect overcompensates for the proposed 'photon fatigue' which would be infinitesimal, since Hubble's deep field showed that light from very very far away is still powerful enough to reach the telescope.

And for the theoretical: we may indeed have a theory that works on known physics with no new interactions required, but we also still have a lot of question marks out there, like for example Dark Energy. This is said to aid in the accelerated expansion of the universe, but we know nothing of Dark Energy. Who's to say that it's not aiding photon fatigue instead?

[imatfaal]

Nizzle

Andromeda is 2.6 MLyr away - surely that's not so small as to be unmeasurable?  Absorption lines are very accurate and the amount of red shift is very nicely measureable. 

Yes - the current theory needs extra effort and some tweaking; the accelerated expansion is not the least of our problems.  But the difficulties of the present theory are limited - any new theory must lessen the number of inponderables