The difficulty is to explain the facts that at the furthest from our view Galaxies are receding fastest of all. Thus they display even larger redshifts of light than normal .

Have we a logical explanation without inventing unknown masses or forces?

We suggest that in addition to the  usual gravitational explanation for part of the show the remaining extra redshift can be caused by the rotation of the entire universe. This also would explain the movement of galaxies away from each other. Those nearer the centre of the universe, wherever that is, would be imperceptibly affected compared to those closer and closer to the edge .