Recent content by Morbert

For a subsystem constantly interacting with its environment, the stochastic dynamics will be divisible. They can be defined in terms of undivided stochastic dynamics in the sense that we can ignore the divisibility of the dynamics. But that doesn't mean it isn't there. And to reiterate: It is...

This timestamp might be of interest, where he discusses dynamics of subsystems vs the entire universe.

See section 3.7 here. Transition maps are the entirety of dynamics in this formalism, and system-environment dynamics (equation 44) give rise to transition maps between conditioning times called division events (equations 56-58) in subsystems Albert considers (Napoleon and libraries with books...

It's quite simple: Transition probabilities, not standalone probabilities, make up the nomological content of the reformulation. No completion is needed. I suspect Albert just subjectively wants the formalism to look a bit more like Bohmian mechanics. The transition probabilities of subsystems...

It is the case in Barandes's formalism. Consider for example a simple model of the Stern-Gerlach Experiment with initial particle, pointer and environment states ##\ket{\psi}##, ##\ket{\omega}## and ##\ket{\epsilon^+}## respectively.$$U(t'\leftarrow 0)\ket{\psi}\ket{\omega}\ket{\epsilon} =...

At the timestamp, Barandes remarks on the distinction between standalone probabilities and transition probabilities, the latter of which make up the objective dynamics of subsystems Albert concerns himself with, like the earth and Napoleon. The "jumping around" from branch to branch that Albert...

"Bound to be unsatisfactory" needs to be unpacked. There are objective conditions of a good interpretation of quantum mechanics: Empirically adequate, unambiguous, generalizeable to all quantum theories (e.g. QFT). A good few interpretations meet these conditions. Then there are subjective...

See this timestamp, where he distinguishes the dynamical conditional (transition) probabilities from the epistemic standalone probabilities.

Equation (56) from this paper is an example of a subsystem's transition matrix divisible at ##t'##. The transition matrix ##\Gamma^\mathcal{S}(t\leftarrow t')## on the left hand side will have the form (as per equation 1)$$\Gamma^\mathcal{S}_{ij}(t\leftarrow t') = p^\mathcal{S}(i,t|j,t')$$In a...

I don't understand this paragraph Division events will give rise to more than probability distributions. They will give rise to directed conditional probabilities that make up the dynamics of the theory. And these directed conditional probabilities will prohibit the world from jumping from...

If by no-collapse interpretation you mean interpretations that do not posit collapse as a physically real process, then consistent/decoherent histories is a no-collapse interpretation which permits stochastic/probabilistic dynamics.

My obligatory defense of consistent histories The consistent histories formalism is nonstandard in the sense that the construction of history operators is somewhat novel. But all the underlying machinery is standard QM (Hilbert spaces, projectors, density operators etc). A choice of framework is...

As an aside: When we write Bell states like $$\ket{\psi} = \frac{1}{\sqrt{2}}(\ket{\uparrow}_1\ket{\downarrow}_2 + \ket{\downarrow}_1\ket{\uparrow}_2)$$The labels 1,2 are not strictly particle labels, but instead addressable mode labels. I.e. A spin-measurement doesn't tell us something like...

There are established probabilistic interpretations distinct from objective collapse, and far more mainstream (to the extent that interpretations can be mainstream). Asher Peres's modern treatise "Quantum Theory: Concepts and Methods", Julian Schwinger's opening essay in "Symbolism of Atomic...

What is the relation between this paper and your previous work on the thermal interpretation? [edit] - I see section 10.6 probably answers this question.