There is (was) a very interesting debate going on online about quantum physics and the nature of reality. You can follow it here and here and here and here.
The Many Worlds Interpretation of Quantum Physics is a very interesting and persuasive idea, there are an infinite number of parallel universe all of whom share a common origin and whose paths diverged at some point in the past. If you have never heard of it then check out the two videos I have embedded.
I do not want to comment on the details of the entire debate since most of the debators are vastly more experienced and qualified than me. However I will mention here my older post where I treat the issue in more detail.
I do feel that in such online debates the crucial points from both sides are sometimes lost in translation. I agree with Philip Ball that MWI is saying nothing new and game changing. Rather it is just a alternative and completely compatible way of looking at nature of reality of the world. Also since it is indistinguishable experimentally from other viable interpretations, it is a philosophical curiosity and not scientific derivation. Carroll’s claims that MWI is self-evident and the ‘correct’ method therefore seems a little over-zealous to me.
However I disagree with a couple of Philip’s objections to MWI, specifically that MWI erases personhood. If the universe is splitting practically at every instance, many of which contain a nearly identical version of you, then who is the real you. This is a (philosophical) problem. But MWI does not create this problem, it is inherent in Quantum physics.
If the electron can go both right and left at the same time, which way did the electron really go? Consequently, the experimenter could be seeing the electron go left or right, should not the experimenter also be in a superposition, of having seen the electron go left and right at the same time.
That is the basis of the Schrodinger cat paradox, can a cat be truly dead and alive at the same time?
MWI simply says yes because the dead cat and alive cat live in two separate universes and our act of seeing the cat somehow splits us in one of those two universes and we can never see the other universe.
The Copenhagen interpretation says there is only 1 universe, the cat is in a weird fuzzy dead and alive state and our measurement collapses it into a recognizable state, either pet or roadkill.
To me both views have their own brand of weird, and since they are experimentally indistinguishable to our current knowledge, equally valid. One universe with superpositions or multiple universes with no superpositions, either way quantum physics stays just as counter-intuitive and just as correct.
I don’t see any need to be dogmatic about a philosophical argument, and therefore I must agree with Philip since he seems to believe that as well.