Physicists provide support for retrocausal quantum theory
The many-worlds interpretation of quantum mechanics is the only one that&#x27;s easy to understand.  All others seem to bend over backwards to realistically explain quantum effects.  It&#x27;s so rare to find clear explanations, but they do exist.<p>My favorite from David Deutsch, a main creator of the idea of quantum computing:<p>To those who still cling to a single-universe world-view, I issue this challenge: 
explain how Shor’s algorithm works. I do not merely mean predict that it will work, which is merely a matter of solving a few uncontroversial equations. I mean provide an explanation. When Shor’s algorithm has factorized a number, using 10^500 or so times the computational resources than can be seen to be present, where was the number factorized? There are only about 10^80 atoms in the entire visible universe, an utterly minuscule number compared with 10^500.  So if the visible universe were the extent of physical reality, physical reality would not even remotely contain the resources required to factorize such a large number. Who did factorize it, then? How, and where, was the computation performed?