Is there really any problem with an infinate regresion of universes?

[Anomalocaris]

why do you suppose infinite regress means "our" universe, whatever that means, fluctuates?  

The regress is still there if each universe has a definite beginning, and can have an variable and in principle open ended evolution, but the instantiation of the universes has no definite beginning.

Do you mean that each individual universe has a beginning but that the substratum from which one comes, whether we think of such an entity as physical or not, simply "is" in a way that eliminates "was" and "will be"? If motion is without beginning or end, won't we have on our hands something like eternal recurrences where all possibilities that can be exhausted are in fact so, ad infinitum?

Basically.