Is Space Expansion 100% proven?

[waterfall]

In a counterpart of General Relatlvity called Field Theory of Gravitation where spacetime is really flat and spin-2 fields cause gravity. See:

http://arxiv.org/pdf/gr-qc/9912003v1.pdf

Space is already there as the following description state:

"Cosmology is another field of application of gravitation theory. Present data about large scale galaxies distribution contradict to the main point of Friedmann cosmology — its homogeneity. It turned out that galaxies form a fractal structure with dimension close to 2 at least up to the distance scales bout 200 Mpc. This leads to a new possibilities in cosmology (see an analysis of FTG cosmological applications in the review of Baryshev et al., 1994). One of the main difference between FTG and GR is that the field approach allows the existence of the infinite stationary matter distribution (Baryshev, Kovalevskij, 1990). In a stationary fractal distribution the observed redshift has gravitational and Doppler nature and is not connected with space expansion as in Friedmann model."

Is there a possibility the above is the case and space didn't really expand but as I interpretated from the above.. space is already there? Or is space expansion 100% proven already beyond the shadow of a doubt? Thanks.

 

[bapowell]

Wow. I'm amazed how wrong the 2nd sentence in the abstract is. The FRW cosmology describes a homogeneous universe. Is our universe homogeneous? That depends on the scale: on the scale of stars and galaxies, it is far from homogeneous. However, on the scale of the observable universe, owing precisely to the "fractal" nature of galaxy distribution, the universe is well-described by the FRW cosmology.

A stationary cosmology is going to have a hard time dreaming up the CMB and BBN.

 

[clamtrox]

First of all, physics does not "prove things 100%", so the answer to your topic is no.

Wow. I'm amazed how wrong the 2nd sentence in the abstract is. The FRW cosmology describes a homogeneous universe. Is our universe homogeneous? That depends on the scale: on the scale of stars and galaxies, it is far from homogeneous. However, on the scale of the observable universe, owing precisely to the "fractal" nature of galaxy distribution, the universe is well-described by the FRW cosmology.

Actually there has been some legitimate research done in this area, and there is some tension between FRW models and observations, see for example http://arxiv.org/abs/arXiv:0805.1132. I do agree with you that the sentence is ridiculous, but on a scale of wrongness, it could be more wrong :-)

A stationary cosmology is going to have a hard time dreaming up the CMB and BBN.

and BAO, and fitting all of them together.