3
votes
0answers
39 views

Why can't Wetterich's “Universe without expansion” be tested compared to standard cosmological redshift?

I have read on several sites that this is a theory that cannot be tested. Why is this a theory that can not be tested? It seems to me that if the mass of particles is continually increasing, then the ...
6
votes
1answer
121 views

What are the different ways to measure the spatial curvature of the universe?

Just what the question asks. Assuming the Friedmann-Rovertson-Walker (FRW) metric, what measurements can be performed to determine the spatial curvature of the universe.
2
votes
0answers
42 views

Are there multiple ways to determine the redshift of the CMB experimentally?

I know that by using Boltzmann equation and all that one can calculate that photons become decoupled around T~3000K and because temperature scales as T~1/a we can determine that the redshift of the ...
4
votes
1answer
119 views

Why is there a line in the middle of the Planck full sky map?

Why there is a straight line (or perhaps a flat surface) in the middle of the Planck full sky map? and zoom (it makes it seem that the big bang was a collision between two unknown surfaces)