Ulla Mattfolk Do you have a link to that explanation. If amplitude in your case is not physical, what is then physical in the SO state? I don't grasp your explanations.
This isn't "in my case" it's just basic QM. Amplitude is a mathematical component of the quantum state, modeled in a wave function, that generates Born rule probabilities for physical quantities. My essay does assume an acquaintance with QM theory, so if you'd like to understand the difference between an unobservable, basis dependent, complex coefficient in the wave function and an observable physical quantity then you can consult your local library to get a start.
Ulla Mattfolk Now you want to have SO (God or godless does not matter to me, but God is a good metaphor) WITHIN the universal wavefunction, but you have several times pointed out it should be OUTSIDE and this was even a fundamental thing in your model...
When defining the SO I clearly state first up it's a "theoretical view" and I'm not positing an actual nonphysical god-like entity that sits outside the universal wave function because that would be theology not physics. I also state that the "SO’s view is total, conceptual and encompasses all possibilities, all 'worlds' at once" as opposed to the partial view of the RSO, and that conflating these two views would be a "methodological error" when interpreting the universal wave function.
What that means is that, given an Everettian universe, if you're an 'observer' then you're embedded in \Psi_{\text{U}} and not outside of it (unless you ARE a god!), so you should probably distinguish between 'outside' talk (SO) and 'inside' talk (RSO) in order not to conflate unobservable theoretical entities (other worlds) with the observable empirical world we live in. It's just a point of logic going forward as I develop the RSO empirical view. Forget about gods, think observers and how they view their world.
Ulla Mattfolk This IS a 'collapse'. The main idea was the wave or particle, and the collapse is to form a 'dead' particle, a physicality, from something continous. Borns rule is about this, also an amplitude can be 'collapsed' into a point on a branch, maybe? The idea is to 'make it real' Your RSO is continous, so 'unreal' then...?
I have no idea what you're on about here and don't understand your non-standard language re dead particles (it's all waves), continuous vs discontinuous wrt Born rule which is not about collapse into a point on a branch (which is a component of a superposition) but probabilities.
Everettian interpretations are influential precisely because they don't postulate a collapse mechanism as an added extra to \Psi. There is no physical 'collapse', just superposition decoherence into quasi classical mixtures each of which is a branch. This is standard MWI and if you want an accessible deep dive into that interpretation then Sean Carroll submitted his view here for the 2018 FQxI competition.
