Math of Spreading Wavefunction

[bluecap]

The wave packet or wave function that spreads in time is one reason Schrödinger didn't make it as the particle itself.. and the death of wave particle duality. Also why Born introduced the probability distribution.

For those of us who are Many worlder with their emphasis of the wave function as objective. Some.. or at least I, was misled thinking that the state, represented by the statistical operator, really is in one-to-one relation with the described object. I thought the state vector is the object itself. But it doesn't seem to be that way.
So the worlds in many worlds are only superficial being just subsystems. Anyway. I wonder if any or all spreading wave function can be decomposed into subsytems or many worlds. What is the math of spreading wave function because I want to see if all can be decomposed into many worlds or no connection at all really.

Also what interpretation where the state, represented by the statistical operator, is really is in one-to-one relation with the described object? Is there any.. like is Objective Collapse this or the Cramer's CI, etc. suggesting this? Thanks.

 

[Lord Jestocost]

Quantum mechanics is nothing but a set of calculational recipes designed and used by physicists in order to predict the probabilities of various directly observed macroscopic outcomes (observations), viz. to study and describe – so to speak - the linkage of pointer readings with pointer readings The wave function is thus merely an intellectual tool corresponding to nothing in the - as we call it - „real world“.

 

[bluecap]

Quantum mechanics is nothing but a set of calculational recipes designed and used by physicists in order to predict the probabilities of various directly observed macroscopic outcomes (observations), viz. to study and describe – so to speak - the linkage of pointer readings with pointer readings The wave function is thus merely an intellectual tool corresponding to nothing in the - as we call it - „real world“.

Yup I am realizing that. But after two branches occur, we still have spreading wave function and still need the Born Rule in each branches.. so Many World doesn't solve fix Copenhagen by making all eigenstate real... it still needs Copenhagen in each Many worlds. And I just want to confirm this by knowing what is the equation of spreading wave function look like.. and want to know if it always involve worlds/branches inside the spreading wave function ?

 

[bluecap]

Yup I am realizing that. But after two branches occur, we still have spreading wave function and still need the Born Rule in each branches.. so Many World doesn't solve fix Copenhagen by making all eigenstate real... it still needs Copenhagen in each Many worlds. And I just want to confirm this by knowing what is the equation of spreading wave function look like.. and want to know if it always involve worlds/branches inside the spreading wave function ?

Or to be clearer.. spreading wave function means spreading probabilities since wave function is about probabilities. So in Many Worlds.. the spreading wave of probabilities is simply spreading wave of branches or entangled subsystem. The word "World" gives illusion of nut and bolt world.

Why do objects look they way they do.. like bolts and nuts.. I tend to think objects are made of state vectors or probabilities.. but it is not. So what is an object made of?

 

[vanhees71]

Objects are finally made of the elementary particles of the standard model (as far as we can say from our present understanding) but not of vectors or probabilities since these are abstract notions to describe them on the fundamental level.

 

[bluecap]

Objects are finally made of the elementary particles of the standard model (as far as we can say from our present understanding) but not of vectors or probabilities since these are abstract notions to describe them on the fundamental level.

But elementary particles are only described by vectors or probabilities.. so what are elementary particles (quarks) made of really? even fields are just operators...

 

[vanhees71]

The elementary particles are described by all the mathematical things needed to formulate the Standard Model, but they are not themselves mathematical abstracta. What an elementary particle like an electron "really" is, is a quite empty question, because you cannot not reduce it to simpler ideas. An electron to our present understanding it elementary, i.e., it cannot be described by anything simpler. An electron from the physicists' point of view is defined as something that has all the properties of an electron, i.e., a certain mass of about $511 \mathrm{keV}/c^2$, spin 1/2, electric charge $-e$, and it's a lepton, i.e., taking part in the electroweak but not the strong interaction (and of course gravity, but that everything carrying energy and momentum does).

 

[kith]

even fields are just operators...

For fields, too, the map is not the territory. But the terminology is a bit confusing. I started a thread on this a couple of years ago.