Yes. Many worlds is the single obvious solution. It seems some people don't understand many worlds though. Or maybe there is some other definition I am not aware. I want to describe my understanding here for people's benefit.
The idea is that when you make an observation nothing special happens at all. For one, there is no wave function collapse. This is more an idea about how the observer experiences making a measurement. The salient feature is that the observer is not external to the system. He is a part of the system. His belief that the result was heads or tails is coincident in the wave function with the coin being heads or tails. In other words, the user becomes entangled with the system.
A toy wave function would look like this (I am leaving off normalization since I can't write a square root of 2):
Coin flip result, no observer:
|heads> + |tails>
Coin flip with observer, "Tom":
|heads>|Tom: it was heads> + |tails>|Tom: it was tails>
There is no collapse here. However, to Tom it appears as if the world did collapse. For the "version" of him that thinks the coin flip came up heads, his entire world is consistent with the measurement coming up heads.
I assumed most people who really understand quantum mechanics believe this (but I may be wrong). And that among them, there is no effort to say "There is no collapse" because indeed the effective result of the measurement is a collapse. I also use the language "wave function collapse" to describe what happens. This not because it is an objective reality of the universe but because it is the way we observe the universe.
That was my understanding too. It's disappointing that it keeps getting explained along the lines of "every time there's a decision point at the quantum level, the universe splits in two", when it doesn't say anything of the sort (at least, not if I've understood it correctly).
The idea is that when you make an observation nothing special happens at all. For one, there is no wave function collapse. This is more an idea about how the observer experiences making a measurement. The salient feature is that the observer is not external to the system. He is a part of the system. His belief that the result was heads or tails is coincident in the wave function with the coin being heads or tails. In other words, the user becomes entangled with the system.
A toy wave function would look like this (I am leaving off normalization since I can't write a square root of 2):
Coin flip result, no observer: |heads> + |tails>
Coin flip with observer, "Tom": |heads>|Tom: it was heads> + |tails>|Tom: it was tails>
There is no collapse here. However, to Tom it appears as if the world did collapse. For the "version" of him that thinks the coin flip came up heads, his entire world is consistent with the measurement coming up heads.
I assumed most people who really understand quantum mechanics believe this (but I may be wrong). And that among them, there is no effort to say "There is no collapse" because indeed the effective result of the measurement is a collapse. I also use the language "wave function collapse" to describe what happens. This not because it is an objective reality of the universe but because it is the way we observe the universe.