About QM Interpretations

[lorin_f]

When we locate a particle, what we are actually doing is performing a local measurement during which we succeed to interact with the particle. Therefore, would this interpretation be plausible:
1. Particles spread the whole universe, in the sense that their wave functions assign a probability to interact with it during measurements for every place in the universe.
2. What the wave function represents is actually the probability of an interaction with the particle at a given place. There is no other meaning to "location". This argument seems to be supported by the EPR experiment, where it may be argued that we interact (with a particle pair in this case) on two different locations at once.
3. Interactions affect the wave functions. 
With this interpretation, apparent paradoxes involving locations and wave nature of particles seem to disappear, and instead different aspects of the wave function in various circumstances can be considered, such as interference or collapse of the wave function. Also, the speed of light limit is not violated.

[Carrock]

As no one else has replied I'll have a go...

4 hours ago, lorin_f said:

When we locate a particle, what we are actually doing is performing a local measurement during which we succeed to interact with the particle. Therefore, would this interpretation be plausible:

You've already assumed a major part of the Copenhagen interpretation i.e. the Heisenberg cut unless you accept that a local measurement does not require non local collapse of the wave function.

Your points all assume the Heisenberg cut and implicitly the Copenhagen interpretation which is very convenient but is already an interpretation.

 

Quote

The cut is named after Werner Heisenberg's work on the Copenhagen interpretation of quantum mechanics in which it is associated with wave function collapse.^[6] Interpretations of quantum mechanics that do not recognise wave function collapse (such as De Broglie–Bohm or many-worlds interpretations) do not require Heisenberg cuts....

 

...For this reason there must, within limits, exist complete freedom in choosing the position of the dividing line.

The Heisenberg cut is chosen so that it defines a measurement in a convenient way.

An old example of the Copenhagen interpretation:

Wigner's friend is inside a sealed box which itself contains a sealed box with a cat which is fed* if a radioactive atom decays.

The cat knows whether the atom has decayed because it is hungry/not hungry.

 Wigner's friend opens the cat box and the superposition of hungry/not hungry cat collapses for him but not for those outside the box.

Later Wigner's box is opened and the superposition of hungry/not hungry cat collapses for everyone.

So three different instances of waveform collapse caused by a single (possibly non) event. Decide which is the real collapse and define the Heisenberg cut to make it so.

I don't see anything wrong with your interpretation if it assumes the Heisenberg cut but there are others on this forum who know more about this than I do.

 

 

 

*no cats were harmed during this experiment.

[MigL]

You'd better open those damn boxes and feed the poor cat.
No cats were harmed, my a*s !
( I'm a cat lover; what can I say )

[studiot]

I don't accept that Schrodinger's cat is a very good example since it is possible to circumvent the 'paradox'.

 

Remember also that the architects of Copenhagen knew and stated that it was 'rough round the edges' i.e. it was incomplete but that it was the best they could do at the time.
Sadly time has not yet matured it into a better interpretation.
Perhaps one day we will have enough information to complete the jigsaw picture.

Edited December 28, 2018 by studiot

[Strange]

10 minutes ago, studiot said:

Sadly time has not yet matured it into a better interpretation.

Wikipedia has a list of nearly 20 interpretations: https://en.wikipedia.org/wiki/Interpretations_of_quantum_mechanics 

Maybe one of them is better? (Whatever "better" means; I guess like all analogies some work better for some cases but others are better in other cases.)

[studiot]

15 minutes ago, Strange said:

Wikipedia has a list of nearly 20 interpretations: https://en.wikipedia.org/wiki/Interpretations_of_quantum_mechanics 

Maybe one of them is better? (Whatever "better" means; I guess like all analogies some work better for some cases but others are better in other cases.)

Perhaps I should have said full understanding.

 

[Carrock]

1 hour ago, studiot said:

I don't accept that Schrodinger's cat is a very good example since it is possible to circumvent the 'paradox'.

 

Remember also that the architects of Copenhagen knew and stated that it was 'rough round the edges' i.e. it was incomplete but that it was the best they could do at the time.
Sadly time has not yet matured it into a better interpretation.
Perhaps one day we will have enough information to complete the jigsaw picture.

I was describing the Copenhagen interpretation specifically.

I don't see any 'paradox.'

For e.g. Schrodinger's cat, you simply place the arbitrary Heisenberg cut between quantum system and classical observer for a wave function collapse at a place/time which is convenient for calculations. One such cut would include only the radioactive atom and detector, everything else treated as classical. For most measurements this is a simple, practical approach.

I haven't considered other interpretations which require wave function collapse but I can't see any of them having an unambiguous wave function collapse without some very dubious assumptions.

[studiot]

2 hours ago, Carrock said:

I was describing the Copenhagen interpretation specifically.

I don't see any 'paradox.'

No, the OP did.

But you introduced the specific cat 'paradox'.
I have always udnerstood that this came after Copenhagen as a sort of toungue in cheek response to show how weird or even downright ridiculous and peverse quantum theory can be.

The cat question was "is  the cat alive or dead at a particular point in time before we have interacted ?" (ie opened the box).

 

[MigL]

While the "cat in the box' interpretation has its flaws, I think Carrock was specifically discussing which interaction collapses the wave function.
And how they are all suitable ( but flawed ); whether it's the radioactive decay, opening the inner box, or the outer box.

[Carrock]

On 12/28/2018 at 8:50 PM, MigL said:

While the "cat in the box' interpretation has its flaws, I think Carrock was specifically discussing which interaction collapses the wave function.
And how they are all suitable ( but flawed ); whether it's the radioactive decay, opening the inner box, or the outer box.

What I'd have said, only better, if I hadn't been offline for a while.

[Carrock]

20 hours ago, Carrock said:

What I'd have said, only better, if I hadn't been offline for a while.

I meant MigL said it better than I would have... [/foot in mouth]

[stephaneww]

Mr. Heisenberg is at the vet's for his cat. The latter said to him: Sir, I have a good news and a bad news for you. I start with which?

 I go out

[Martyred Goat]

Now i don't think i quite have my head around the topic at hand.... but i am hopefully getting there. My thoughts for now are this. 

The inclusion of any math based on probability highlights the inclusion of things that can't be accurately measured. However, if the outcome of the occurrence is measurable, then there must be a cause for that outcome. I believe that any "dice role" is just cause and effect we can't yet see. 

If you meet an identical copy of me in another place, many would start saying that there must have been a possibility for me to exist in multiple locations. But its also possible that i haven't ended up in multiple locations. The actual probability needed to be calculated is the chance of identical atoms arranging themselves in an identical way. I occurred once "by chance" So i could occur twice. Both me having two positions and the universe producing two versions of me must be included.

If there is nothing but you a pencil and empty space. Is the pencil shrinking? are you growing? or is the distance increasing? If you have no other information.... Is there any difference between the 3? 

I may be miles away from your question, What i'm trying to say is that the situation likely includes factors that we won't grasp for a while, Information we don't yet have. The interpretations are a means to work out what can't work. Specifics are increasingly seeming like a non-concept.

[Strange]

1 hour ago, Martyred Goat said:

The inclusion of any math based on probability highlights the inclusion of things that can't be accurately measured. However, if the outcome of the occurrence is measurable, then there must be a cause for that outcome. I believe that any "dice role" is just cause and effect we can't yet see. 

This is a "hidden variables" model. This is ruled out by Bell's Theorem.

Also, the fact that things are probabilistic, doesn't mean they can't be accurately measured. We can measure to whatever precision our technology allows.

[studiot]

2 hours ago, Martyred Goat said:

I may be miles away from your question, What i'm trying to say is that the situation likely includes factors that we won't grasp for a while, Information we don't yet have. The interpretations are a means to work out what can't work. Specifics are increasingly seeming like a non-concept.

That also applies to understanding probability, which is a very misunderstood subject.

2 hours ago, Martyred Goat said:

The inclusion of any math based on probability highlights the inclusion of things that can't be accurately measured. However, if the outcome of the occurrence is measurable, then there must be a cause for that outcome. I believe that any "dice role" is just cause and effect we can't yet see. 

(nearly) Agreed.

Formal probability is a limit to infinity of the effect of a number of trials.

Yes some trials  can only be performed once and some have never been performed.

Further certain p values, particularly 0 and 1 lead to some bizarre results.

 

[studiot]

Thank you for the upvote, whoever.

Some additional comment or question would have been nice.

So here is one.

In a truly infinite series of trials, how many times will a specific event occur, given that the event has a non zero probability, however small ?

[Martyred Goat]

On 1/23/2019 at 8:55 AM, Strange said:

This is a "hidden variables" model. This is ruled out by Bell's Theorem.

Also, the fact that things are probabilistic, doesn't mean they can't be accurately measured. We can measure to whatever precision our technology allows.

Anything probabilistic without 100% certainty involved... is an inaccurate measurement :p 


 

On 1/23/2019 at 12:00 PM, studiot said:

Thank you for the upvote, whoever.

Some additional comment or question would have been nice.

So here is one.

In a truly infinite series of trials, how many times will a specific event occur, given that the event has a non zero probability, however small ?

You're welcome  

I will likely often be blocked by the daily limit... will be tough to balance between number of posts and length of responses... 

Easy question to answer... ish... With perception not limited, there are an infinite number of identical events. With any limit to perception, Then there is no way of knowing that any given event is not you counting the same event twice. 

I will assume limitless perception, And so the event occurs repeatedly and is easily distinguishable from the other identical events (via the portions in between). The amount of other data in between is also easily distinguishable.... So its also simple enough to calculate the frequency of the given event.

Any limit to perception brings the perceived number of events down from infinite. (i think)

[swansont]

13 minutes ago, Martyred Goat said:

 I will likely often be blocked by the daily limit... will be tough to balance between number of posts and length of responses... 

That limit only applies to the first day. (it's an anti-spam measure)

[Strange]

1 hour ago, Martyred Goat said:

Anything probabilistic without 100% certainty involved... is an inaccurate measurement

Tossing a coin is a probabilistic event, yet we know whether the result is heads or tails.

[Martyred Goat]

1 minute ago, Strange said:

Tossing a coin is a probabilistic event, yet we know whether the result is heads or tails.

And if we know its trajectory, spin and the shape/texture of the surface it lands on. Then we know which way up it will land. It is only probabilistic when we can't calculate the variables involved which will lead to the outcome. In theory there is a chance of it being heads or tails. In actuality. It will only be one of the two. And that outcome is determined by the variables which are measurable. 

Its only a probabilistic event when you assume there are unknown variables. It becomes a determinable event if all variables are measured and the outcome is calculated.  

[Strange]

36 minutes ago, Martyred Goat said:

Its only a probabilistic event when you assume there are unknown variables. It becomes a determinable event if all variables are measured and the outcome is calculated.  

There was a famous paper by Einstein, Podolsky and Rosen (EPR) that said: either there are hidden variables (your suggestion) OR particle attributes (such as position, velocity, energy, polarization, etc.) are not real and defined until they are observed. Bell's theorem shows that the presence of hidden variables would produce different results from the predicted by QM. And this has been confirmed by experiment. Therefore no hidden variables and therefore the values of these properties are not defined until we measure them.

A fairly readable overview in this article: https://drchinese.com/David/Bell_Theorem_Easy_Math.htm

Quote

In it simplest form, Bell's Theorem states: 

No physical theory of local Hidden Variables can ever reproduce all of the predictions of Quantum Mechanics. 

 

[studiot]

1 hour ago, Martyred Goat said:

Easy question to answer... ish... With perception not limited, there are an infinite number of identical events. With any limit to perception, Then there is no way of knowing that any given event is not you counting the same event twice. 

I will assume limitless perception, And so the event occurs repeatedly and is easily distinguishable from the other identical events (via the portions in between). The amount of other data in between is also easily distinguishable.... So its also simple enough to calculate the frequency of the given event.

Any limit to perception brings the perceived number of events down from infinite. (i think)

 

I have no idea what you mean, but I do know that probability and its mathematics does not work like that.

Unknown quantities, which may be unknown simply because we have not yet bothered to measure them and hidden variables are not the same thing either.

It would be good if we could all work from the same set of definitions of words.

 

We used to have a goat here called Nimrod, who changed his name.

I had thought you were perhaps the new name for this member, but apologies as I seem to be wrong about that.

Edited January 24, 2019 by studiot

[Martyred Goat]

1 minute ago, Strange said:

There was a famous paper by Einstein, Podolsky and Rosen (EPR) that said: either there are hidden variables (your suggestion) OR particle attributes (such as position, velocity, energy, polarization, etc.) are not real and defined until they are observed. Bell's theorem shows that the presence of hidden variables would produce different results from the predicted by QM. And this has been confirmed by experiment.

A fairly readable overview in this article: https://drchinese.com/David/Bell_Theorem_Easy_Math.htm

 

And so "every action has an equal an opposite reaction" is incorrect? 

Is it not possible that an illusive variable both leads to the given outcome and a positive result from the calculations that show there is no illusive variable? 

Seems to me like there is a question - Why did that happen?

And from what you are saying, the answer is - It happened without cause.

I'm quite comfortable with "Not real or defined until observed" But for me..... when they are defined, something determines what it is that they are defined as. Even the presence of "literal random" Is by definition a hidden variable. Instinct is telling me that they looked everywhere and didn't find a hidden variable... I won a game of hide and seek once...... I'm still there :p 

I shall review bells theorem post haste, 

[Strange]

2 minutes ago, Martyred Goat said:

And so "every action has an equal an opposite reaction" is incorrect? 

I don't see the connection. (And no.)

Quote

Is it not possible that an illusive variable both leads to the given outcome and a positive result from the calculations that show there is no illusive variable? 

It would be up to you to show how that could happen.

3 minutes ago, Martyred Goat said:

Seems to me like there is a question - Why did that happen?

And from what you are saying, the answer is - It happened without cause.

I'm not sure this is directly related to causality. But there are events that happen without cause, so that's not a problem.

 

[Martyred Goat]

13 minutes ago, studiot said:

 

I have no idea what you mean, but I do know that probability and its mathematics does not work like that.

Unknown quantities, which may be unknown simply because we have not yet bothered to measure them and hidden variables are not the same thing either.

It would be good if we could all work from the same set of definitions of words.

 

We used to have a goat here called Nimrod, who changed his name.

I had thought you were perhaps the new name for this member, but apologies as I seem to be wrong about that.

In a truly infinite series of trials, how many times will a specific event occur, given that the event has a non zero probability, however small ?

Any defined event will occur an infinite amount of times. If its probability is anything above zero then you keep going until it happens again.

A hidden variable is an unknown quantity, An unknown quantity is a variable, but it may not be hidden. I think we are using the same definitions :/ 

3 minutes ago, Strange said:

I don't see the connection. (And no.)

It would be up to you to show how that could happen.

I'm not sure this is directly related to causality. But

 

Urm.... "every action has an equal an opposite reaction" is clearly incorrect if anything can occur without cause. 

-------------------

How that could happen.... Simulation  I'll try and get something more specific after i have read up on bells theorum

-------------------

"There are events that happen without cause, so that's not a problem."

You are saying there is a reaction with no action. So you are arguing against newtons third law.

Now i don't mean to sound argumentative....... But..... THERE ARE NO EVENTS THAT HAPPEN WITHOUT CAUSE!!! ...... Even if a property exists.... and that property allows for the occurrence of events without a cause.... then that property is the cause.... 

Please provide an example of an event without a cause. I will give everything i own to conclusive proof that you can get something from nothing