(June 23, 2016 at 2:32 am)Alex K Wrote:(June 22, 2016 at 5:48 pm)bennyboy Wrote: Okay, a kind of relativity question:
If the forces in the universe were the things changing and distance being constant, rather than vice versa, such that everything was actually shrinking, couldn't this give the exact some sense of redshift and the illusion of motion? It seems to me that if the receptor has shrunk in size, it will sense light as being longer in wavelength, and therefore lead to the inference of motion due to red shift, though perhaps none has occurred. Would there be anyway to differentiate experimentally between these two possibilities?
Yes, when you do the math of the Standard model living in an expanding universe, you have to make a choice. Either your stick the change of scale which you get from the Friedman equations into the coordinates, which gives you the usual expansion picture, or you absorb it into the fields, forces and masses, which gives you shrinking matter
The latter is much more complicated mathematically, but should be physically equivalent.
As far as I see it, it's a matter of convention without observable differences.
It seems to me there would be at least one important difference: the view on the Big Bang Theory. If you virtually reverse time, even if you scale all matter to an arbitrarily large size, causing overlap, you'd never arrive at a singularity, since that would require an infinitely large scale.
