There is an often-repeated statement that different quantum mechanical theories are equivalent. This is an over-simplification. Is wave function collapse is a real thing or just an approximation of what happens when a large system is entangled? Some smart people have tried to make theories where wave function collapse is a real thing. These new experiments are working to rule out those ideas. My feeling is that Evere…
I don't see how relabelling "collapse" to "separation" and adding more or less infinitely proliferating universes solves the problem. MWI also contradicts itself. Supposedly the universes are independent, but if their influence doesn't define the wave equation they do nothing to help explain it. It's a very strong and exceptional claim with absolutely no evidence to support it. "Feeling" isn't enough.
MWI isn't just renaming the collapse. Copenhagen is fundamentally different in that exactly one outcome is somehow chosen / selected and all others cease to exist. In other words Copenhagen has to add / invent some information: Which world to pick and when to do so. MWI simply avoids having to pick by continuing every branch simultaneously and recursively.
Meaning that MWI is actually a simpler theory and shows that the selection is unnecessary and all problems that come with it can be avoided. In that sense, the burden of proof lies with Copenhagen IMO and it just gives handwavy answers that the selection process somehow involves a conscious observer, whatever that is ...
> MWI also contradicts itself. Supposedly the universes are independent, but if their influence doesn't define the wave equation they do nothing to help explain it.
In MWI the wave function IS the integral of all possible outcomes / worlds / branches. In that sense they don't just influence it, they define it. Not sure how that is contradictory.
Btw, the same goes for Copenhagen in the state of super position as well. So, they are identical up to the point where Copenhagen selects one (collapses) and MWI simply carries on.