Victor Stenger's recent book, The Fallacy of Fine-Tuning: Why the Universe is Not Designed for Us. Stenger claims that all known fine-tuning cases can be explained without the need for a multiverse. Many of Stenger's claims will be found to be highly problematic. ...The prevailing explanations are God and the multiverse:
We conclude that the universe is fine-tuned for the existence of life. Of all the ways that the
laws of nature, constants of physics and initial conditions of the universe could have been,
only a very small subset permits the existence of intelligent life.
The concept of other universes has been proposed to explain why our universe seems to be fine-tuned for conscious life as we experience it. If there were a large number (possibly infinite) of different physical laws (or fundamental constants) in as many universes, some of these would have laws that were suitable for stars, planets and life to exist.The multiverse is not a scientific explanation at all.