How to understand QM. My Christmas present to you

[Mike Helland]

Hi. It's me again.

You may know me from my previous thread "I don't think space is expanding".

Well, here's another idea for you. Background: when I first came up with this, it was in the context of photons work on electrons, and gravitons must work on photons, so .... what we see is actually the output of a machine like that?

At first I thought this was some wild ground breaking idea, but as I talked to others about it, it turns out this is what Plato and Kant and Leibniz and whole bunch of other people were on about, so much so that it's called the "perennial philosophy".

Ok, enough woo. Let's get to the sauce.

Turns out, this is also what Hugh Everett was on about.

* Everett, Hugh, (1957) "Relative State Formulation of Quantum Mechanics", Reviews of Modern Physics, 29: 454462.

For some reason (mainly a dude named Dewitt), everyone thinks Everett was on about many worlds. The "Everett" interpretation and MWI are now synonymous. This is a big mistake.

Here is page 9:

Observation

We have the task of making deductions about the appearance of phenomena to observers which are considered as purely physical systems and are treated within the theory.

It will suffice for our purposes to consider the observers to possess memo- ries (i.e., parts of a relatively permanent nature whose states are in correspon- dence with past experience of the observers). In order to make deductions about the past experience of an observer it is sufficient to deduce the present contents of the memory as it appears within the mathematical model.

As models for observers we can, if we wish, consider automatically func- tioning machines, possessing sensory apparatus and coupled to recording devices capable of registering past sensory data and machine configurations. We can further suppose that the machine is so constructed that its present actions shall be determined not only by its present sensory data, but by the contents of its memory as well. Such a machine will then be capable of performing a sequence of observations (measurements), and furthermore of deciding upon its future experiments on the basis of past results. If we consider that current sensory data, as well as machine configuration, is im- mediately recorded in the memory, then the actions of the machine at a given instant can be regarded as a function of the memory contents only, and all relavant [sic] experience of the machine is contained in the memory.

For such machines we are justified in using such phrases as "the machine has perceived A" or "the machine is aware of A" if the occurrence of A is represented in the memory, since the future behavior of the machine will be based upon the occurrence of A. In fact, all of the customary language of subjective experience is quite applicable to such machines, and forms the most natural and useful mode of expression when dealing with their behavior, as is well known to individuals who work with complex automata.

The symbols A, B, ..., C, which we assume to be ordered time-wise, there- fore stand for memory configurations which are in correspondence with the past experience of the observer. These configurations can be regarded as punches in a paper tape, impressions on a magnetic reel, configurations of a relay switching circuit, or even configurations of brain cells. We require only that they be capable of the interpretation "The observer has experienced the succession of events A, B,..., C."

The mathematical model seeks to treat the interaction of such observer systems with other physical systems (observations), within the framework of Process 2 wave mechanics, and to deduce the resulting memory configura- tions, which are then to be interpreted as records of the past experiences of the observers.

Ok... this dude is literally .... in 1957... saying stuff about modeling a neural network inside a particle simulation.

We clearly are a ways away from doing that in 2020.

No wonder no one had any idea of what he was really talking about.

Over the next 50 years, I think you'll see this concept of a mathematical model making measurements of itself from the inside become self-evident.

For now, people will think this is woo, and go on thinking that parallel universes are real.

 

[Mike Helland]

To me he's saying "on a super computer, make a particle simulation, that contains something like a smart phone (camera and computer vision software) and find out what's in the memory of the smart phone that exists in the memory of the super computer."

This would tell us how the model looks from the inside.

 

[Robin]

Everett stipulated machine observers to scupper the idea that an observer needs to be a conscious human observer. In other words he was shutting down any mystical interpretation that others might put on his work.

Nothing in that requires that there be a computer capable of running the mathematical model (which is almost certainly impossible in any case). All that is required is that we think about and predict what the contents of those memories was, which was perfectly possible in 1957. Nor does he appear to be talking about any sort of simulation.

Often in QM the 'observer' is not specified and this leads to all sorts of confusion in those trying to understand it.

Whenever I am trying to understand any interpretation of QM I always think of the 'observer' as an observer in the sense that Everett describes.

 

[Robin]

Also I have read interviews with Everett which leave no doubt that he was indeed on about many worlds.

 

[Roboramma]

Everett stipulated machine observers to scupper the idea that an observer needs to be a conscious human observer. In other words he was shutting down any mystical interpretation that others might put on his work.

Nothing in that requires that there be a computer capable of running the mathematical model (which is almost certainly impossible in any case). All that is required is that we think about and predict what the contents of those memories was, which was perfectly possible in 1957. Nor does he appear to be talking about any sort of simulation.

Often in QM the 'observer' is not specified and this leads to all sorts of confusion in those trying to understand it.

Whenever I am trying to understand any interpretation of QM I always think of the 'observer' as an observer in the sense that Everett describes.

This.

/thread

 

[alfaniner]

How to understand QM. My Christmas present to you

Umm... thanks, I guess.

Worst gift given or received

 

[Mike Helland]

Whenever I am trying to understand any interpretation of QM I always think of the 'observer' as an observer in the sense that Everett describes.

Right, but Everett wasn't saying we "think" of the observer in the model that way.

He was suggesting we actually model it.

Let the math do the work.

That's why he called it the relative state formuulation. This is not an interpretation. This is a blue print for unique, sophisticated and ground breaking set of computations.

60+ years later, an unsolved programming challenge still exists, and I think it'll be much like a the "singularity" that transhumanists talk about, when it happens.

 

[Thermal]

Everett stipulated machine observers to scupper the idea that an observer needs to be a conscious human observer. In other words he was shutting down any mystical interpretation that others might put on his work.
Nothing in that requires that there be a computer capable of running the mathematical model (which is almost certainly impossible in any case). All that is required is that we think about and predict what the contents of those memories was, which was perfectly possible in 1957. Nor does he appear to be talking about any sort of simulation.

Often in QM the 'observer' is not specified and this leads to all sorts of confusion in those trying to understand it.

Whenever I am trying to understand any interpretation of QM I always think of the 'observer' as an observer in the sense that Everett describes.

Possibly off-topic, but this has always been my roadblock to pursuing a more in-depth understanding of QM. I read Zukav's The Dancing Wu Li Masters way back, and it was clearly meant to be all mystical. Then in school, Schrodinger's Cat was brought up. I of course objected, that the ******* cat was either ******* dead or ******* alive, not in some probability wave till you looked at it. The teacher eventually acknowledged that the analogy wss a steaming pile with no resemblance to what it was meant to analogize. It was a way to picture what the math predicted. But the analogy was useless IMO if it gave a nonsensical or simply wrong image. I recall from calc somewhere that if you get a nonsense answer, you are doing the wrong u substitution or whatever, even if you are doing the math correctly. It means you are just off on an entirely irrelevant reasoning. So these illustrative paradoxes have no meaning to a layperson in the English language, unless you get the math first, in which case you don't need the illustrative paradoxes. Or something.

 

[Mike Helland]

Possibly off-topic, but this has always been my roadblock to pursuing a more in-depth understanding of QM. I read Zukav's The Dancing Wu Li Masters way back, and it was clearly meant to be all mystical. Then in school, Schrodinger's Cat was brought up. I of course objected, that the ******* cat was either ******* dead or ******* alive, not in some probability wave till you looked at it. The teacher eventually acknowledged that the analogy wss a steaming pile with no resemblance to what it was meant to analogize. It was a way to picture what the math predicted. But the analogy was useless IMO if it gave a nonsensical or simply wrong image. I recall from calc somewhere that if you get a nonsense answer, you are doing the wrong u substitution or whatever, even if you are doing the math correctly. It means you are just off on an entirely irrelevant reasoning. So these illustrative paradoxes have no meaning to a layperson in the English language, unless you get the math first, in which case you don't need the illustrative paradoxes. Or something.

To me his treatment of an observer is the most interesting part of the formulation, because the same trick he's applying to wave mechanics should technically be applicable to any system with complex enough output as to contain measurement records from an observer machine.

 

[Ziggurat]

Mike, have you actually ever studied quantum mechanics? I don't mean reading books which try to explain quantum mechanics. I mean actual textbooks that teach you to do quantum mechanics calculations.

 

[Mike Helland]

Mike, have you actually ever studied quantum mechanics? I don't mean reading books which try to explain quantum mechanics. I mean actual textbooks that teach you to do quantum mechanics calculations.

Of course not.

But I can tell the difference between "the Everett interpretation" and the relative state formulation.

One is an interpretation and has many worlds due to the uncollapsed universal wavefunction.

The other is the blue print for a computer program that contains internal observers and tells us what a model looks like from inside of it.

 

[tusenfem]

So, now quantum mechanics is a computer program now?
That would have made studying physics so much more ughhhhhhh

 

[Mike Helland]

So, now quantum mechanics is a computer program now?
That would have made studying physics so much more ughhhhhhh

I mean, you could try to make a mathematical model with a functioning observer on paper or a chalk board if you want, but I don't think that will speed of the process of inventing it.

 

[Ziggurat]

Of course not.

I’m not trying to be rude here, but none of your opinions are actually informed. They cannot be. You don’t actually know what quantum mechanics is, if you’ve never actually done it. That’s like trying to study a language without actually learning to speak it. It will not work.

If you ever do learn to do quantum mechanics, come back and let us know how it went. Until then, nothing you say about it will be of any interest.

 

[theprestige]

The best thing I can say about this thread is that the title follows the mainstream media trend of using "how" or "why" in a headline to a story that fails to explain how or why.

 

[Mike Helland]

I’m not trying to be rude here, but none of your opinions are actually informed. They cannot be. You don’t actually know what quantum mechanics is, if you’ve never actually done it. That’s like trying to study a language without actually learning to speak it. It will not work.

If you ever do learn to do quantum mechanics, come back and let us know how it went. Until then, nothing you say about it will be of any interest.

Ok.

 

[Mike Helland]

The best thing I can say about this thread is that the title follows the mainstream media trend of using "how" or "why" in a headline to a story that fails to explain how or why.

If the measurement problem is "how to think of measurement", then Everett's answer is "model it."

Seems like the most obvious answer to me.

Make a mathematical model of a measurement happening. It'll happen some day.

 

[Myriad]

If the measurement problem is "how to think of model measurement", then Everett's answer is "model it."

I've replaced one short phrase in your original quote with a different word that, in context, has the exact same meaning. I hope this might help you understand why your suggestion is not being perceived as particularly helpful.

 

[Mike Helland]

I've replaced one short phrase in your original quote with a different word that, in context, has the exact same meaning. I hope this might help you understand why your suggestion is not being perceived as particularly helpful.

Oh, well, it's Everett's suggestion, but sure.

Say in your typical model you have two objects, each has a mass, and a position in three dimensions:

var objects = [
    {x: 0, y: 0, z: 0. m: 5}, 
    {x: 0, y: 5, z: 0. m: 5}]

If this was the initial conditions of the model, you could just let it run for bit (apply the rules in a loop), and then check to see where each object is now.

console.log(objects)

What we're doing is determining the absolute state of the model.

Everett was saying we could find the relative state of the model if we do the following:

1. model the objects as a collection of particles
2. include photons in the collection of particles
3. include a clock in the collection of particles
4. include a ruler in the collection of particles
5. include an observer in the collection of particles

The observer should be able to make measurement records purely as a result the initial conditions and rules, nothing special added.

Now, we could console.log(objects) to see the absolute state of the model, from our God's eye perspective.

Or we could inspect the memory of the observer, and that tells us the relative state.

 

[Robin]

Then in school, Schrodinger's Cat was brought up. I of course objected, that the ******* cat was either ******* dead or ******* alive, not in some probability wave till you looked at it. The teacher eventually acknowledged that the analogy wss a steaming pile with no resemblance to what it was meant to analogize.

You and your teacher appear to have missed the entire point of Schrödinger's cat.

It isn't an analogy, for a start.

Also, it was Schrödinger's whole point that the cat was either dead or alive and not in a probability wave until you looked at it. It is a similar to Einstein's gunpowder thought experiment. Schrödinger was asking whether QM was an actual law of nature, or whether it was just a useful calculus.

Perhaps you should look into these matters a little more deeply before assuming that people like Einstein and Schrödinger were complete idiots.