Confirming that Everettian quantum mechanics avoids ‘spooky action at a distance’ addresses longstanding concerns about its compatibility with relativity; however, the researchers acknowledge this work doesn't fully resolve debates surrounding wavefunction branching itself. Some interpretations, like those initially proposed by von Neumann, necessitate an instantaneous collapse of possibilities upon measurement, a concept successfully sidestepped within many worlds theory but still debated amongst physicists.

Still, acknowledging lingering debate over how ‘branching’, the splitting of universes in Everettian quantum mechanics, actually happens is important context for understanding this complex theory. The researchers demonstrate that avoiding instantaneous connections across vast distances remains a key strength of many worlds interpretations despite these ongoing discussions about branching itself.

Researchers at the University of Oxford have clarified how Everettian quantum mechanics sidesteps ‘spooky action at a distance’, addressing concerns about its compatibility with Einstein’s theory of relativity; this work focuses on branching, the splitting of universes within the many worlds interpretation, as an emergent phenomenon rather than a causal process.