Lately, I’ve been trying to gain a better understanding of quantum decoherence. This is the process of a quantum system in superposition interacting with the environment and, as a result, appearing to lose its quantum nature, notably by having interference between the elements of its superposition become undetectable.

Decoherence is often used synonymously with the wave function collapse (including by me in older posts), but they’re generally acknowledged to not be the same thing. Decoherence explains the disappearance of the interference between the superposition states, but it doesn’t address how or why those multiple states appear to collapse or reduce to one, if in fact they do. The ultimate fate of those states is why we need interpretations such as Copenhagen, many-worlds, etc.

One of the struggles I’ve had is that most popular descriptions of decoherence are a bit shallow, and more meaty treatments tend to quickly fall into dense mathematical formalism, usually ending my ability to follow the discussion. Often these accounts discuss how decoherence is a quantum system becoming entangled with its environment.

While that’s true, the jumble of terms led me down a wrong path, assuming an equivalence between coherence and entanglement which doesn’t exist. As a result, I’ve thrown around the word “coherent” incorrectly in both posts and conversations, most recently on my post on quantum nonlocality.

While rooting around online for a good explanation, I stumbled on a post by Chad Orzel noting the effort he had put into the explanation of decoherence in his book, *How to Teach Quantum Physics to Your Dog*. I bought this book several years ago, and had read his description before, but not with my current interest. As it turns out, Orzel’s description of decoherence is the best popular account I’ve come across. Highly recommended! (Though you would have to endure dog and rabbit analogies.)

Orzel uses an interferometer with beam splitters and mirrors for his explanation. But I think most people are more familiar with the double slit experiment. (If you’re not familiar with it, Jim Al-Khalili does an excellent nine minute primer.)

The interference that takes place in this experiment happens because the components of the wave, including the parts that make it through both the top and bottom slit, are coherent with each other, that is, they have a phase relation. That’s a fancy way of saying that the timing is right. The wave propagates everywhere at the same time, so it interferes with itself in the right way to produce the diffraction pattern on the back screen.

Decoherence, the loss of quantum coherence, is simply the timing getting screwed up. This can happen by putting a detector at one of the slits, which uses a magnetic field to detect the particle, slightly delaying propagation of that part of the wave and throwing the timing off.

We might accomplish a similar effect by increasing the distances between the particle gun, the first screen, and the second screen, so that the wave interacts with more air molecules in its journey, causing random fluctuations in the propagation of its components. It can also be induced to smaller or greater extents by having the wave pass through perpendicular electromagnetic waves of varying intensity before reaching the screen.

Surprisingly (at least to me), decoherence does not *end* the interference. The coherency of the wave causes the interference to form noticeable and detectable patterns. When the timing gets messed up, those detectable patterns are disrupted. But the interference itself remains. It’s just fragmented and isolated now and, depending on just how decohered the wave has become, much harder to detect. (It is possible in principle, although it would require knowledge of all the microstates in whatever part of the environment was involved up to that point, so not something happening anytime soon.)

This description of decoherence makes sense, and seems to drain much of the mystery. Decoherence is generally irreversible, but it’s an irreversibility in practice due to the enormous number of moving parts. In other words, while effectively impossible to reverse, it is possible in principle. In fact, if not allowed to progress too far, it actually can be reversed, that is, *recohered*, as a 2015 experiment managed to do.

So, in the quantum nonlocality post, when discussing a “world” under the many-worlds interpretation, I should have stuck to entanglement language. In that sense, a “world” is a state or branch in the composite superposition of an entanglement network, an entity which is nonseparable and therefore has nonlocal states, even if it doesn’t have nonlocal dynamics.

Coherence itself only refers to the state of a wave function that allows the elements of its superposition to interfere with each other. Once the wave is decohered, its role is over. The term “decoherence” often seems used to refer to the sustained wave of entanglement into the environment, but in that broader sense, coherence itself is no longer a factor. Sorry for propagating my confusion on this.

The learning continues. Any pointers would be much appreciated.

[debating with self whether I should get into this, given that Mike is more read on this subject …]

[overcoming my better sense]

First, how strongly do you feel about the statement that “slightly delaying” one of the slits is sufficient for decoherence? I’m pretty sure from my high school physics that, for normal waves, if you tilt the plate with the slits slightly, you do not eliminate the coherence, you just shift the pattern. (Could be wrong.)

Does any of this affect how you think about delayed decision/quantum eraser effects? (Wikipedia: https://en.wikipedia.org/wiki/Delayed-choice_quantum_eraser)

*

LikeLiked by 2 people

Never be afraid to jump in. I obviously was wrong before and can definitely be wrong again.

Would tilting the plate actually cause any delay in the wave’s propagation? I could see it altering the shape on the other side, probably skewing the interference pattern, but I don’t think it would disrupt the timing and phase relation. Unless I’m missing something?

I thought about the quantum eraser when writing this. I think that’s why Orzel used the interferometer setup, because it’s basically the simple quantum eraser setup in that article. At least in the simple version, there’s no disruption in the timing, so no problem when the beams are recombined and the interference returned. However, if you had made one of the paths longer so that there was a timing issue, or even just spaced out the experiment so the beams had to travel through more air, things would be different, and probably couldn’t erase it at the end.

On the more complex version, I don’t know.

But Orzel discusses a double slit version involving polarization filters on the slits. With different filters in front of each slit, the interference pattern disappears. With an added filter behind one of the slits to make its light like that from the other filter/slit, the pattern returns. So this one doesn’t seem like a timing issue. Having different polarizations seems to make a difference, and returning them to the same seems to allow them to interfere. He doesn’t appear to discuss the eraser thing in the section on decoherence. So it’s probably not

justa timing issue.LikeLiked by 1 person

Hi Mike,

Not to muddy the waters, but there’s an article on phys.org entitled “Physicists Find Quantum Coherence and Quantum Entanglement Are Two Sides of the Same Coin.” So how wrong could you have been!?

I’m going to dive into the deep end here, and perhaps muck this up, but I believe James’ comment reflects a common and incorrect inference about phases in quantum mechanics that amateurs like myself make all the time. I think it helps to begin with a review of what classical coherence is: oscillators in synchrony. Now when we look to quantum mechanics and how the mathematics apply to the physical world I think there is a challenge in keeping two things straight: a) the phases of the

wave equation, which in the conventional QM are probabilities of various outcomes of experiment and are not physical oscillators at all; and b) the actual oscillatory phasing of physical particles. We can say the former probabilities are “in phase” when they are mathematically coherent, such as when they are in a quantum superposition, but we are referring to the mathematics of the wave equation and not to physical oscillators. It’s an important distinction.So when we have the double slit experiment without any measurement of which slit a photon passes through, all of the various possible outcomes of the experiment described by the wave equation are “in phase.” They are coherent. And they remain so until the “measurement” is made at the detector screen. But they’re not (to my understanding) entangled.

Now if you use some device to determine which slit the photon passed through, you’ve effectively made a measurement, and because you’ve done so the wave function has “collapsed.” (Let’s leave MWI aside for just a moment.) You determined where the particle was, and so all subsequent measurements must be consistent with this one, so the interference pattern goes away, and the mathematical corollary to this is that we’ve lost the coherence of the wave equation. (I guess in an overly simplified sense, ignoring the processes of decoherence, the other possibilities for this experiment all go to zero and the measured outcome goes to a probability of 1 so there are not multiple mathematical entities to be in phase any longer.) This has nothing to do with the physical photon or electron being in phase with itself or not–I don’t believe–and everything to do with the fact that the potential outcomes of the wave equation, which once were in phase, and were coherent, are no longer so.

I think if you don’t make the measurement at the screen, you can do all sorts of things and still get an interference pattern–such as angle the detector screen so it’s not perpendicular to the screen with the two slits in it, or stagger the slits slightly, etc…

Decoherence is enigmatic, but I’ll try… Unlike the simplified version I wrote about, I don’t think decoherence posits the sudden non-existence of the other possible outcomes of a measurement. I think it posits that information about one of the possible outcomes is retained while information about the others is frittered away in the environment and “lost” in some sense. But mathematically, this involves a decoherence of the various possibilities described in the wave equation.

Michael

LikeLiked by 3 people

Well put. The mathematical phases he mentions is the e-to-the-i-something stuff I blogged about recently. (It’s exactly this math that makes decoherence discussions so mathematical.) The quantum phase is a vector that spins around like a clock hand, but the length of the vector is always the same, so the

magnitude(the probability of finding the photon if looked for) is constant (equally probable) everywhere.With two slits those “clocks” meet (images like the one in the post are plots of the quantum phase). The areas where the waves cancel aren’t cases of “negative” and “positive” energy meeting and canceling. They’re places where the quantum phase information meets and interferes (thus changing the magnitude of the combined vector). The cancellation zones are zones of low probability.

Moving the parts of the experiment (laser, slits, screen) changes the pattern just as it would if done with water or sound waves. The distances matter. (For instance, the slits have to be close enough together to be covered by the photon’s spreading wave-function.) What’s so different is what the waves

mean. Classical waves are energy waves. Quantum waves are… something we currently treat as probabilities.I just finished re-reading

Through Two Doors at Once(2018), by Anil Ananthaswamy. It’s a whole book about the two-slit experiment (and related inferometer versions). Some of them are quite amazing. One of the last he discusses is the experiment in the Canary Islands where a single entangled photon was sent from La Palma to Tenerife. It’s a very interesting sophisticated delayed-choice experiment involving entanglement.LikeLiked by 2 people

Hi Michael,

Thanks for the reference to that phys.org article. Here’s a direct link for anyone else interested: https://phys.org/news/2015-06-physicists-quantum-coherence-entanglement-sides.html

I’m not sure what to make of this, but I don’t think it rescues the way I was using coherence. I certainly didn’t have the complex concepts outlined in this article in mind. And this snippet makes me think the situation is very nuanced.

You make a distinction between the wave function mathematics and physical reality. I’m sure you know that depends on your stance toward the ontology of the wave. It’s interpretation dependent. “Weak” Copenhagen and other interpretations such as RQM and QBism have an anti-real stance. But “strong” Copenhagen, the MWI, and GRW all have a realist stance.

Here, my inclination has always leaned realist, at least to some degree. It certainly seems like something generates the interference effects. I’ve never understood how a mathematical mechanism could do that.

There seems to be pretty good consensus that decoherence doesn’t address the other outcomes. It seems to account for the disruption of the coherence and loss of interference effects due to the system becoming entangled with the environment. The significance of that last part depends on which interpretation you favor.

But everything is controversial in this area.

LikeLiked by 2 people

Hi Mike,

Yes, I understand the different interpretations of the wave equation you describe, and don’t know which way I lean to be honest. I kept with the double slit experiment example because that was what you’d used in your post and begun to discuss with James; that said, I’m no expert on the mathematics but I think there are any number of things the wave equation could represent that would not lend themselves to the same intuitive notion of a wave traveling through space, but could still have a range of physically valid probable outcomes that are described by the equation, and are in phase with one another, until whatever it is that happens… collapse or MWI branching or decoherence… happens. Wyrd may have to help us out here. But we could have a wave equation that describes an electron (in an atom), that has been excited and has a chance of emitting a photon and dropping to a lower energy state, or a wave equation describing the possible spin states of a particle like a photon. The possible states that could be measured in these cases could be coherent just like possible locations of detecting a photon in the double-slit experiment, but it’s a little harder to think of these as physical waves in space like it is for the double-slit experiment.

The double-slit experiment is a situation that lends itself to mentally placing the wave from the wave equation into the position of

being the light itself, but I think if we look at other scenarios in QM I think it becomes apparent this is not what the wave equation is, in any interpretation of QM, whether real or anti-real. The wave equation describes possible outcomes in a phase space, and in the mathematics of the wave equation these states can be said to interfere with one another, but is that the same as saying the particles themselves interfere with one another…?An issue that is challenging with regards to thinking of the wave equation as physically real is Born’s Rule. As we know, it is the square of the amplitude of the wave at a point in space or time that gives the probability of witnessing a particular outcome, so in those interpretations that use the wave equation with Born’s Rule in this way, the wave isn’t itself a physical carrier of a specific property. It’s a description of possible results. That’s the anti-real version, I know. In MWI, all outcomes are real, but the question remains: what is the wave physically? If we have a wave equation that in MWI gives all possible outcomes to an experiment that measures the spin of a particle, the wave is still not the spin of the particle–it is still a mathematical formalism that describes possible outcomes, or to say it another way, that describes trajectories of a system through some sort of phase space, right? It’s just that in MWI they’re all assigned a probability of 1. All points in phase space are real. But what exactly

issuch a wave? In this case it is a description of multiple real particles that exist simultaneously in all possible states into which the initial conditions of the “experiment” could evolve. But what is such a wave?We know it’s a wave, even in MWI, because interference patterns are produced in the double-slit experiment that are the product of “worlds” interfering with one another in a wavelike manner. But on the other hand, it’s not a wave at all, it’s simply many particles existing in possible trajectories. Can it be both at once? How do all of these “real” particles interfere with one another? And if they don’t, but it’s the wave equation interfering with itself (e.g. the coherent states are interfering), then how can all the particles it describes in MWI be said to be real? The wave equation would remain a description of possible positions in phase space, and how could such a description be physically real?

I think when we remove our considerations from the configuration of the double-slit experiment, it’s not nearly as intuitive to imagine the wave equation as a physical wave traveling through space in time. And I think that’s so regardless of interpretation to some extent. I could envision a description of MWI, for instance, in which all possible outcomes of an experiment described by the wave equation are physically real (in some world), but the wave equation still is not. Because again, how can something be physically real that is a description

aboutsomething else. Isn’t this, at some level, like taking the odds book for a horse race that describes possible outcomes and their likelihoods, and conflating it with the horses themselves?This is very confusing, and all the more interesting for it… I don’t expect these comments to hold up well in the light of history, but it’s enjoyable to wonder about such things. 🙂

Michael

LikeLiked by 2 people

Again: Well said.

“The double-slit experiment is a situation that lends itself to mentally placing the wave from the wave equation into the position ofbeing the light itself, but I think if we look at other scenarios in QM I think it becomes apparent this is not what the wave equation is, in any interpretation of QM, whether real or anti-real.”Yes, exactly. That’s what I was getting at above. The waves we see in plots of the two-slit experiment are that phase, which is a rotation of a vector in complex space. Because we’ve all see those diagrams of light waves — the electric and magnetic fields — we tend to visualize the two-slit experiment in those terms.

But that’s not correct. The dark bands are not places where the energy of two waves has cancelled out. That would be saying the photon effectively vanished. The dark bands are places of low probability. As you say, we further interpret those waves through the Born rule. (I agree that makes it harder to understand what the Schrödinger equation is saying.)

So I think it’s a very good point that different experiments help steer away from seeing the two-slit phenomenon as interfering EMF waves. The various interferometer experiments are generally two-slit experiments in disguise.

LikeLiked by 1 person

Hi Michael,

I totally agree it’s all very confusing. And I’ll admit when it comes to something like spin, my sense of how a superposition of spins states could be physical isn’t there. But then, quantum spin is a very strange thing anyway. The spinning ball pictures are misleading. What does it mean physically to say a particle has 1/2 or 5/2 spin?

I also think we have to be careful when talking about the wave function, because you’re right, it is a description. Wave function ontics, I think, doesn’t refer to the mathematical function itself, but to whatever it is modeling, which I often just use “wave” without “function” to refer to. It seems possible that some aspects of it are physical while others are relations between physical phenomena. But the wave function seems able to predict the overall dynamics with profound accuracy.

All that said, it isn’t just the double slit experiment that makes me think there’s a physical reality there. Too much science and technology are built on the dynamics. And then there’s the success of quantum computing. I know the anti-real interpretations have narratives for it all, but they seem convoluted, strained to me. All in all, it seems easier to account for quantum computing if there is a physical reality to what’s happening.

The question of what the wave might be made of is difficult. Deutsch, in the context of the MWI, does say the wave is a wave of particles, just with each particle in its own “universe”. Alternatively, we can look at the particles as fragments of the wave. What the wave might be in objective collapse theories seems more difficult since it’s some kind of entity prior to its collapse into a particle. The wave itself might make more sense if we drop to quantum field theory, where everything is a field excitation and everything is about fields interacting. Of course, then we get into the question of what is a field? Strings? Branes? Turtles?

There is a lot of hand wringing about how to talk about probabilities with the MWI. We can look at it as they map to the proportions of “worlds” with the outcome, or to the energy level of different “worlds”, or a host of other ways that all amount to different ways of talking about the same ontology. Carroll thinks of it as the probability of which branch we’re on after the measurement but before we know the result. One nice aspect of Deutsch’s way of looking at this is, with preexisting “worlds”, we can just talk about the probability of the result in our “world” without getting mired in semantics.

LikeLiked by 1 person

Thanks, Mike.

As sometimes happens in our discussions I find myself returning to the beginning to see how we got here, and the primary point I was trying to make is that when talk about coherence for outcomes described by the wave equation, we are talking about phasing relative to that mathematical construction, not

necessarilyto physical waves. Theremaybe elements of physical reality that correspond to the terms in the equation, but no interpretation we now have–whether realist or anti-realist–yet enables an experimental test of this. I could be wrong on that, but that’s my understanding?You wrote,

All that said, it isn’t just the double slit experiment that makes me think there’s a physical reality there. Too much science and technology are built on the dynamics. And then there’s the success of quantum computing. I know the anti-real interpretations have narratives for it all, but they seem convoluted, strained to me. All in all, it seems easier to account for quantum computing if there is a physical reality to what’s happening.The fact remains that all of the science and technology may be accounted for with any interpretation of QM as I understand it. I haven’t thought about it too much before, but can see the ease of envisioning quantum computing in the MWI approach. The math of QM clearly has profound predictive power, but it has precious little explanatory power, and so this is a case where it seems many would agree the map may or may not accurately reflect the territory. We just don’t know yet.

So that’s my only real point: that the map is not necessarily the territory in this case. When we speak of coherence with respect to terms / possible observable states predicted by the wave equation, that’s very definitely

notthe same as the physical coherence of a population of oscillators that produces a laser beam. A population of atoms that emits laser light due to coherence is in many ways classical–the only quantum piece being the discrete energy levels between excited/ground states of the atoms–and this is every different than a coherent superposition of possible states in a quantum system, only one of which will be actually observed when we look. They are both described as coherent because there are “waves” and “phases” involved, but I think they’re very different phenomena?Michael

LikeLiked by 2 people

PS – speaking about mathematics vs reality, I don’t know if you and Wyrd saw this article on Quanta about how the block universe requires infinite information (e.g. infinite significant digits mathematically), but I thought it was interesting and may be to you guys as well…

LikeLiked by 2 people

Thanks Michael. I hadn’t seen that article before. Interesting.

One thing I was struck by in the article, is how many people cited quantum mechanics with the standard interpretation as support for their ideas. Many people want interpretations to just go away, but for better or worse, they do matter, and I don’t think we have the option of ignoring them.

LikeLiked by 1 person

Hi Mike, I missed the emphasis on interpretation in the article. Was it related to a specific point? And agreed, we cannot ignore them as they make different claims about nature.

A related/tangential question: the MWI does not resolve the fundamental differences in how time appears in QM and GRT does it? That still remains a conundrum?

Michael

LikeLiked by 1 person

Hi Michael,

No emphasis on interpretation, just that everyone who cited quantum mechanics assumed wave function collapses.

On differences in time, since the MWI is just QM without the collapse, and QM has been mapped to QFT, it’s good with special relativity. With GR, gravity is in the mix, so I wouldn’t think so.

LikeLiked by 1 person

I pretty much read everything Natalie Wolchover writes there!

That, and another article in 2019, got me thinking about a deterministic universe (let alone a block one). Determinism assumes infinite precision, and it’s a very good question where that precision is supposed to come from. It’s got me pondering whether the real numbers don’t apply to reality.

(Reality might not be real, but at least it’s rational. 😀 )

LikeLiked by 1 person

Just read it again and was reminded how much it struck me. If Gisin is right it would explain a great deal. I’m very attracted to the physicality of the idea. That example about 0.49999… is similar to Philip Ball’s Twenty Questions game and in general seems aligned with the information view Ball ends up suggesting seems fruitful.

LikeLike

Thanks Michael.

Many of the pioneers in quantum computing theory are/were MWI supporters, and some do claim QC validates the MWI. But it seems like any interpretation with a realist stance toward the wave, like GRW and other objective collapse theories, works as well. It is true that as the number of qubits scale, the MWI account will increasingly sit more easily with what’s happening. But I don’t know that QC, in and of itself, will ever conclusively prove the MWI.

I agree. The map is not the territory. But as I noted to Lee, we have no access to the territory. We only have the inferences built up from observations and summed in the mathematical models, models that have been heavily tested for decades. The underlying reality could be incomprehensibly different, but our only path to knowing about it seems to go through those models.

On the coherency of waves and laser light, there are probably nuances I’m not aware of, but I do know that to do the original double slit experiment (Thomas Young’s version) at home, you need a coherent light. A white light won’t create the pattern. It all needs to be at the same wavelength.

LikeLiked by 1 person

So, no it from bit? 😉

LikeLiked by 1 person

I have to admit I don’t really understand the “it from bit” phrase. It seems like I’ve seen different explanations of it.

LikeLike

I’d take the implication entanglement and coherence are the

samewith a grain of salt:They’re talking about a relationship between them and the ability to convert between entangled states and coherent ones. They mainly connect them as two kinds of superposition:

Which is true as far as it goes. As the article describes, when a coherent system can be split, as in a two-slit experiment, the coherent parts are in superposition and can interfere.

But the mathematics of the two are notably different.

LikeLiked by 2 people

FWIW: In

Beyond WeirdPhilp Ball talks about the information view of quantum mechanics (which he likes). I don’t know that I’m sold on it, but does simplify a lot of explanations. Knowingwherethe particle is, or even that itisa particle, removes enough information from the system that there isn’t enough to create an interference pattern anymore. QED.(Yeah, okay fine, but what is the ontology of information? Even elementary particles obviously have many of these information bits.)

LikeLiked by 1 person

I can’t say I’ve found the information approaches compelling, but I have to admit I’ve only read quick summaries of most of them, notably QBism. And one thing I’ve learned repeatedly is quick summaries are not a good way to judge a theory. I do have Ball’s book and read portions of it a while back. If he gives a good treatment of them, maybe I need to revisit it.

A key question for me is what kind of information are we talking about? The summaries of QBism talk about personal beliefs which…sounds strange.

LikeLiked by 2 people

Ha, yeah, I don’t know what to make of QBism. There are some parts I kinda like, but I’m not convinced Bayesian view of statistics is anything but frequentism-in-progress.

One thing I learned from Ball’s book is that I’m a “quantum reconstructionalist” — it’s the view that QM is, at best, incomplete or, at worst, just plain gone down a wrong path, and so

all“interpretations” should be tossed (because what a strange idea that we need to “interpret” a theory) and we should focus on trying to figure out what’s physically going on starting from the ground up.(Informational views are part of that. “It from bit” and Ball’s version, “if not is”. I do find his Twenty Questions example very interesting.)

LikeLiked by 1 person

Starting over? It’ll be interesting to see if they’re able to come up with something truly different.

It does seem like a good idea to always regard a scientific theory as incomplete. We should probably be suspicious when anyone says that this is it, there is nothing else to see here. In that sense, I wouldn’t be surprised if QM / QFT is someday superseded by an improved theory. The difficulty, of course, is that any successor has to meet all the predictive successes of its predecessor, and then improve on them, or at least achieve the same success with fewer assumptions.

Although I wonder if any successor theory will actually be any less weird, or if it will just pour gasoline on the weirdness.

LikeLiked by 1 person

Michaels’ explication here is right on target and thorough. To briefly summarize: There is an unassailable difference between the reality of a mathematical equation and the true nature of Reality which the math is suppose to represent. In laymen’s terms, math is an analogy and/or metaphor; nothing more. And in my opinion, everyone places too much weight on math (analogies) and not enough preponderance on the explanatory power of the evidence based solely upon the structure of intelligence.

Intelligence should be the final arbiter on such matters however, my research suggests that the heartless, cold and benign structure of pure intellect takes a back seat to the vibrant, enriching, life giving valences that dominate our decision making processes. Richard Feynman labeled the mystery surrounding the infamous inference pattern in the double-slit experiment “the only mystery in Quantum mechanics”.

There is some “thing” that is causing the interference pattern, I do not think that conclusion is up for debate. However, it should not be dismissed that there is an unknown quantum world that underwrites our known classical world, and it should be self-evident that this quantum world is what causes the interference pattern, not a particle or wave interfering with itself. The total vacuum of space is NOT an empty void consisting of NO THING. My conclusion can be verified by the observed evidence of the inference pattern itself, a pattern that is observed in the double-slit and further verified by a measuring device placed at one of the slits. The measuring device destroys the quantum reality that is responsible for and causes the interference pattern. This explication corresponds to the intrinsic structure of our universe being both a quantum and classical world as well as the intrinsic structure of our own intellect, a tool that is used to make a logical deduction based solely upon the preponderance of evidence.

There is no mystery to the infamous double-slit experiment and there is no magic, things like this have a reasonable explanation if one is willing to set aside our unreasonable valences and consider the cold, hard facts as we know them. Here are the facts: There is an unknown, unobservable quantum world that underwrites our classical world. If we were not aware of this world, we would be justified in believing that a particle is interfering with itself. But here’s the conundrum: We know that quantum world exists and yet, we are still unwilling to let go of this notion of a particle interfering with itself. Really, I think this refusal is directly correlated to the misconception of a probability equation being the reality instead of a mathematical equation being a “representation” of that reality.

Peace

LikeLiked by 2 people

Lee,

I don’t think anyone disputes that the mathematical description is not the reality in and of itself. (Well, some do, but they’re coming at it from a mathematical platonist framework.) But the difficulty is that we can’t look around the mathematic model to see the underlying reality. The quantum realm is inaccessible to our direct senses.

The only thing anyone can do is make observations and then make inferences from those observations. The mathematical model represents the sum of all those inferences, and has been tested, perhaps more than any other theory in science.

So, that other tool is available for us to be intelligent about it? We can use logic, but math is basically quantitative logic, so we’re already doing that. We can talk about it using language, but here the metaphors become far fuzzier and we lose precision. (Although honestly, most of us are stuck here anyway.)

It seems like our ability to say anything about the quantum reality goes through the math. What other mechanism do we have?

LikeLike

“The mathematical model represents the sum of all those inferences, and has been tested, perhaps more than any other theory in science.”

What you are referring to Mike is the predictive power of those models, and if predictive power is all anyone is really interested in then everything else becomes moot; end of conversation.

“It seems like our ability to say anything about the quantum reality goes through the math.”

You are correct on this one point: “It seems like it…” But do not forget; the only thing that mathematical models “prove” is the math; just like the only thing that analogies “prove” are the analogies: End of conversation.

“What other mechanism do we have?”

How about the pure structure of intelligence void of competing valences. I guess this leads us back to your previous post about epiphanies huh? Math is a creation of the mind. A better alternative to math is explanatory power, an explanatory power predicated upon viable, pragmatic assumptions. Currently there are only two acceptable assumptions, both of which lead to absurdity; materialism and idealism. Try inventing another assumption, one that has the capacity to accommodate both materialism and idealism. Any more questions?

Peace

LikeLiked by 1 person

I should add that the ridiculous metaphysical positions of both materialism and idealism are derived from the dominant influence of valences upon our reasoning processes, a qualia driven dynamic that is in direct contrast to the pure structure of intellect.

Intelligence should be the final arbiter in such matters, but homo sapiens have not evolved to the point where intelligence overrides the dominant influence of valences. Pardon my French here folks, but according to our current paradigm, a paradigm fundamentally grounded in survival and self preservation: “If one cannot eat it, drink it or fuck it; what good is it?”

Be at peace my internet friends and have a safe and happy New Year, free of COVID…

LikeLike