As with Penrose’s model, Steinhardt and Ijjas’s model faces the philosophical problems of an infinite universe, and it must rely on a large number of questionable assumptions. Their effort to construct a model to explain the universe is perfectly reasonable, so I have no criticism of their sincerity or their competence. Yet the conclusion that the universe had a beginning is far more parsimonious and consistent with the evidence. The main reason for the resistance against it from many in the scientific community is its philosophical and theological implications.
Brian Miller, “Paul Steinhardt’s Cyclical Cosmology Fails to Challenge a Cosmic Beginning” at Evolution News (January 12, 2022)
The paper is open access.
While we are here, wouldn’t an infinite universe include the possibility that it doesn’t exist? Playing with infinity is playing a dangerous game.
There is a good article by Robert J. Marks on the topic of infinite parallel universes here.