I think this is a little tricky as the theory uses the actual continuum for wave functions such that the amount of information is and remains infinite whether we remove far-away branches or not.
On the other hand, we can only ever calculate finite approximations of the true thing and here we definitely can be more or less efficient.
When we “collapse the wave function” during a measurement process, we decide to remove the other branches from our description such that in some sense a pragmatic version of hardly computing any of the pilot wave is the standard approach.
The description of Open Quantum Systems has really helped formalize this perspective and one can find that even just cosmic radiation or gravitational interaction is strong enough to create quick branching of the wave function for anything macroscopic.
Unfortunately a mathematically equivalent simplification is not feasible as technically the distant contributions are not ruled out to become important at some point in the future (e.g. the wave function tends to spread out in configuration space such that in a non-expanding universe we would expect branches to touch at some point), but at least for many situations one can get good effective descriptions which put us closer to a quantum-native description of how classical behaviour comes about. From that perspective, the probabilistic predictions tell us about which part of a simplified pilot wave (/many worlds branch) we expect to update towards.
I think this is a little tricky as the theory uses the actual continuum for wave functions such that the amount of information is and remains infinite whether we remove far-away branches or not. On the other hand, we can only ever calculate finite approximations of the true thing and here we definitely can be more or less efficient.
When we “collapse the wave function” during a measurement process, we decide to remove the other branches from our description such that in some sense a pragmatic version of hardly computing any of the pilot wave is the standard approach. The description of Open Quantum Systems has really helped formalize this perspective and one can find that even just cosmic radiation or gravitational interaction is strong enough to create quick branching of the wave function for anything macroscopic. Unfortunately a mathematically equivalent simplification is not feasible as technically the distant contributions are not ruled out to become important at some point in the future (e.g. the wave function tends to spread out in configuration space such that in a non-expanding universe we would expect branches to touch at some point), but at least for many situations one can get good effective descriptions which put us closer to a quantum-native description of how classical behaviour comes about. From that perspective, the probabilistic predictions tell us about which part of a simplified pilot wave (/many worlds branch) we expect to update towards.