When learning about the cosmological Timescape model I see that it takes into account the inhomogeneity between voids and matter-dense regions and may explain the appearing acceleration of the expansion of the universe without a cosmological constant.
One assumption of the Timescape model is that in the voids, time runs faster than in the matter-dense regions.
The Timescape model is relatively new. In contrast, dark energy and, more so, dark matter are older concepts. Before the Timescape model, it was assumed that the universe is homogeneous. The Timescape model takes into account inhomogeneities. My question is whether the assumptions of the Timescape model, if evidence is found for it, would have any influence on what we think about dark matter as well.
In the space between the galaxies, there's also less matter, less gravity, and therefore, time runs faster there. If we are looking from a matter-dense region into regions where time runs faster - it would look as though moving objects there were faster than without the difference in time dilation.
Now, I'm wondering whether the Timescape model, if evidence is found for it, could possibly also account for a certain portion of the dark matter effect as well? Of which order of magnitude would such an effect be for galaxies? Which portion of the aberrant rotation velocity of stars in galaxies may be explainable by different time dilation?
