Why God and the Multiverse, contrary to popular assertion, are indeed compatible.
|"We condemn the proposition that God can not create many worlds."
Condemnations of 1277, Article XXXIV
A general summary of Multiverse theory will be our starting point. The bullet points of this summary are already organized for us, by cosmologist Maximilian Tegmark.
Level I: Space Outside the Observable Radius
In the sense that the Universe can be defined as the Observable Universe, the rest of it outside the observable radius can be defined as a Multiverse of sorts. Most data show our Universe to be approximately "flat" (Euclidean, or nearly so) and thus spatially infinite despite its finite age. Because it is the same Universe spatially extended, the entire Level I Multiverse necessarily originated in the same Big Bang as did the Observable Universe.
Level II: 11-Dimensional Hyperspace and Future-Eternal Inflation
This is an 11-dimensional space with numerous, and perhaps infinitely many, 3-dimensional surfaces or bubbles. These surfaces each constitute a Universe within this Multiverse, and some of them are in fact Level I Multiverses in and of themselves. Although eternal in the future, inflation has been shown (even in 11 dimensions) to be past-incomplete, meaning that it had a beginning. Look up Bord-Guth-Vilenkin (2003) and later works by cosmologist Alexander Vilenkin, for more information on why the Level II Multiverse still had a beginning.
Level III: Alternate Timelines
This level consists of alternate futures based on different outcomes of past events. While associated with the Everett Interpretation of Quantum Mechanics, the reality of alternate timelines was argued by scientists and philosophers long before the Everett Interpretation was published. Because it comprises alternate futures from the same past, this level has the same beginning as Level I.
Level IV: Ultimate Ensemble
Also known to philosophers as the Set of All Possible Worlds, this level consists of all logically and mathematically self-consistent would-be Universes and Multiverses. This is the only level without a beginning, but that is of no concern to the 1st Cause Argument due to its potentiality. The Level IV Ultimate Ensemble consists of potentiality rather than actuality.
Here ends Tegmark's Hieararchy of Multiverses. As Christians, we can accept this hierarchy, conceding only that God is the sole Level V entity. God actualizes as many potentialities as may please him. The Level IV Ultimate Ensemble, also called the Set of All Possible Worlds, is merely potential based on logical and mathematical consistency. If we may imagine God the Creator as a painter, the Set of All Possible Worlds is his canvass, his paint, and his brush, all in one.
Furthermore, a Christian should not say that God is limited to creating only a single Universe. That proposition, as shown in our opening quote, was condemned in the Condemnations of 1277.
Objection 1: "Why bother? The Multiverse is only a statistical argument against design!"
The Argument for God does not require Design but rather stems from Existence itself. As explained above, Levels I, II, and III each have a beginning, while Level IV consists of potentiality. A Creator turns potentiality into actuality however often he wills it.
Objection 2: "The Condemnations of 1277 refer to many worlds, meaning planets. Planets, not Universes."
In 1277 when these Condemnations were written, Earth was not considered a planet. It was thought to be the center of the Universe, with the Heavenly Spheres (stars, comets, and planets) being composed of an exotic substance called Quintessence. Like any document from their era, the Condemnations of 1277 must be read in the context that "world" and "universe" are effectively synonyms.
Quod Erat Demonstrandum.