# How can the many worlds interpretation be deterministic?

Lunct
So the many worlds interpretation describes every quantum events as a branch point, where in which all events happen.
I'll use the example of a coin toss to illustrate my question.
If I flip a coin, I create a branch point in my universe from which two universes emerge, where both heads and tails occur. But, if the many worlds interpretation is deterministic then how could I have two different outcomes coming from the same universe, with the same conditions determining the outcome of the coin toss? Surely, for something to be deterministic, only one thing could have happened. If it is possible for two things to occur from the same event, then the event is based on chance, and not determined.
It would then, in accordance to Bell's inequality, follow that either hidden variables can't exist within the interpretation, or locality is violated.

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So the many worlds interpretation describes every quantum events as a branch point, where in which all events happen.
I'll use the example of a coin toss to illustrate my question.
If I flip a coin, I create a branch point in my universe from which two universes emerge, where both heads and tails occur. But, if the many worlds interpretation is deterministic then how could I have two different outcomes coming from the same universe, with the same conditions determining the outcome of the coin toss? Surely, for something to be deterministic, only one thing could have happened. If it is possible for two things to occur from the same event, then the event is based on chance, and not determined.
It would then, in accordance to Bell's inequality, follow that either hidden variables can't exist within the interpretation, or locality is violated.
There is only ever one universe. After the coin flip it has an entanglement between the state of the coin (Heads or Tails) and the state of whatever interacts with the coin (state of interacting with a Head and state of interacting with a Tail). E.g. you might look at the result, and become entangled where your states are "saw a head" or "saw a tail" etc.

Mentor
@Lunct please do not post interpretations questions in the main QM forum. They should go in the interpretations sub forum