Alternate-universe theory is attractive for several reasons. As a (former) physicist, I find it appealing because it would provide consistent answers to several nagging questions about quantum indeterminacy, and a couple that arise from the requirement to use complex numbers to represent real phenomena. As a Christian, I like it because it helps to answer one of the oldest of all puzzles: how God can be omniscient while Man still has free will. How could a thinking man not love a conception like that?
But I seriously doubt that a way to test alternate-universe theory will ever be discovered. Not in this universe, anyway!
Freedom, Wealth, and Peace,
Francis W. Porretto
Eternity Road