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FQXi Administrator Zeeya Merali wrote on May. 28, 2015 @ 18:41 GMT
@NatureNews
A couple of months ago we spoke with quantum physicists Martin Ringbauer and Alessandro Fedrizzi of the University of Queensland, in Australia, on the podcast, about their experiment looking into the nature of the wavefunction. Their results lend support (though not quite definitively) to “Psi-ontic models” that say that, if there’s an objective reality, then the wavefunction is real. Psi-ontic models include Many Worlds, Bohmian mechanics and collapse models. That’s as opposed to “Psi-epistemic models” that say that the wavefunction just reflects our ignorance about the state of reality. I recently wrote an article for Nature that rounds up various experiments—including that Australian one—that are trying to uncover quantum reality. The full article, “What is Really Real?” on Nature’s site, so please take a look. (The image is taken from Nature's twitter feed: @NatureNews.)

When I attended a quantum foundations meeting in Erice, Italy, sponsored by COST, last March, I was surprised to find that the participants were mainly split between Bohmians and Collapse Model fans. Anecdotally, I’d say that Many Worlders dominate FQXi meetings. I’ve already highlighted collapse models on the blog and podcast, but I wanted to take this chance to flag up a podcast special recorded in Erice with Shelly Goldstein of Rutgers University and Jean Bricmont of the Catholic University of Louvain, who explain what Bohmian mechanics is and present their case for why they believe that it makes the most sense — and talk about why they feel it hasn’t had a fair hearing over the years.

Free Podcast

Bohmian Rhapsody: Physicists Shelly Goldstein and Jean Bricmont discuss features of the deterministic alternative to standard quantum mechanics proposed by David Bohm. From the Quantum Foundations meeting in Erice, Italy, supported by COST.



LISTEN:







Go to full podcast

In the Nature article, I mention the oil droplet experiments that have been getting a lot of attention over the past couple of years because they appear to show droplets “walking” along an oil surface, guided by their own ripples, analogous to the predictions made by Bohmian mechanics. (See the “Pilot Wave Hydrodynamics" forum thread, suggested by John Merryman.)

But there were a couple of other tests to note, which didn’t make the final cut. Bricmont pointed me to the first, which was published in Science. Bohmian mechanics, unlike standard quantum theory, says that particles have definite locations, even before they are observed, and it makes predictions for the paths taken by these particles as they move through, for instance, the double slit experiment. In 2007, Howard Wiseman, a quantum physicist at Griffith University, came up with a way to sneakily track the paths taken by photons in a double-slit experiment using “weak measurements” that allow physicists to quickly peek at an experiment while it is in progress. This disturbs the photon’s location slightly, so no single measurement can indicate where the photon would have been, had it not been observed. But by repeating the test many times, it is possible to build up a statistical picture of the “classical trajectories” taken by photons through the apparatus, which is just what a team led by Aephraim Steinberg at the University of Toronto, Ontario, did, in 2011.

The paths they found tended to correspond with those calculated using the Bohm model, a similarity that Steinberg told me he found “thought-provoking”. The experiment, he said, “underscores the elegance of the Bohm model,” though he added that it does not serve as proof of the interpretation. That’s because the trajectories are not seen directly while the experiment is in progress, but inferred after the experiment has taken place and all the results are in. A Many-World’s fan could thus argue that the trajectories only represent where the particles would have been *if* they took classical trajectories, rather than showing the definite trajectories they actually took. Bricmont agrees that experiment doesn’t prove Bohmian mechanics, but feels that the similarities are striking enough that the results should inspire more physicists to take another look at Bohmian theory.

Owen Maroney, a physicist at Oxford University, also highlighted a paper by Samuel Colin and Antony Valentini at Clemson University in South Carolina, who last year analysed a modified version of the model and calculated that it would have led to a subtly different pattern of quantum fluctuations in the early universe than is predicted by conventional quantum theory and the Many-World’s interpretation (arXiv:1407.8262v1). These signatures could show up in measurements of the cosmic microwave background currently being made by the Planck satellite.

As I mention in the Nature story, there are hopes that it could be just a matter of months before an experiment is carried out that completely rules out Psi-epistemic models and favours Psi-ontic models. But even if that is successful, there is another quantum interpretation that I didn’t cover in the article that would not be affected one way or the other by such tests, even though it is not a Psi-ontic model: quantum Bayesianism (or QBism). This is a relatively recent model based on classical Bayesian probability theory that rejects the notion that the results of quantum experiments can directly access an external objective reality that is independent of the agent making the measurements. According to Q-Bists, the results of quantum measurements are intimately tied to the presence of an agent and serve to change the agent’s degree of belief about what their personal future experience will be.

I asked Ruediger Schack, a QBist at Royal Holloway University in London, about why QBism escapes. He explained that is because the definitions of Psi-epistemic and Psi-ontic — and the wavefunction reality tests — are valid within a specific framework, called an ontological model (by Nicholas Harrigan and FQXi’s Robert Spekkens). “In this framework, outcome probabilities of measurements are determined by some real property lambda. Such models used to be called hidden variable models,” said Schack. QBists, however, do not subscribe to this framework. The Copenhagen interpretation also lies outside this framework.

Maybe it’s time to do a survey. What’s your favourite quantum interpretation? And you think there will ever be a test that could help people choose between various interpretations? Could there be a test that would make you change your mind?

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william m. wrote on May. 28, 2015 @ 19:51 GMT
My interpretation isn't explicitly stated, but probably relates most closely to QBism. It is Max Planck's view: "I regard consciousness as fundamental. I regard matter as derivative from consciousness. We cannot get behind consciousness. Everything that we talk about, everything that we regard as existing, postulates consciousness." ~ Max Planck. I take "Observer" & "Consciousness" to be synonymous terms. In other words, the Observer/Observed distinction is, at root, false. Moreover Consciousness/Observer is not really multiple - e.g., Schrodinger: "Multiplicity is only apparent, in truth, there is only one mind [consciousness]...." Strictly speaking, physics investigates experience. The field of all experience is consciousness. Nature is, in essence, Consciousness.

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Peter Warwick Morgan wrote on May. 28, 2015 @ 20:21 GMT
The comments on the Nature article are pretty comprehensive, some of them practically monographs... It seems better to start from one aspect of Matt Leifer's blog post, http://mattleifer.info/2011/11/20/can-the-quantum-state-be-i
nterpreted-statistically/
, which offers three choices quite clearly (there might be more, but at least he's not reducing the choices to an excessively narrow dichotomy),

"1. Wavefunctions are epistemic and there is some underlying ontic state. Quantum mechanics is the statistical theory of these ontic states in analogy with Liouville mechanics.

2. Wavefunctions are epistemic, but there is no deeper underlying reality.

3. Wavefunctions are ontic."

As Matt puts it, ruling out #1 leaves us with #2 and #3 as choices, and it's hard to see any possible way to rule out #2, which was pretty much the party line for the first 50 years of QM, while leaving #3 intact. [I don't especially agree with Matt's overall discussion in that blog post, but that's another story.]

In any case, no-one seems to be clear enough which Hilbert space we're supposed to think holds the ontic Psi.

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FQXi Administrator Zeeya Merali wrote on May. 28, 2015 @ 20:31 GMT
Thanks William and Peter.

Peter, I also really like Matt Leifer's post, but I had some involved discussions with some QBists who weren't entirely happy with the wording for option 2 that "there is no deeper underlying reality" -- though they did agree that they should be categorised with Copenhagen, as far as these reality tests go.

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Peter Warwick Morgan replied on May. 28, 2015 @ 22:07 GMT
FWIW, Zeeya, I'd like to see this distinction between different Psi-epistemic writ large when this recent strand of discussion about QM is written about. I think Matt managed pretty well to make the distinction in a quite elementary way without getting enmeshed in too much detail.

QBism, very roughly as an intellectual descendent of Copenhagen, doesn't give much room for caviling at "there is no deeper underlying reality". What did they want instead? Another alternative, 2b, instead of going "deeper", "there is an emergent reality (that is as solid as our experience)"? But details are better than slogans.

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Member Matthew Saul Leifer replied on May. 29, 2015 @ 01:44 GMT
I used to be a QBist, but then I recovered.

QBists are sticklers for terminology, but I tried to phrase things in a way that your ordinary Daily Mail reading physicist on the street would understand. QBists think quantum mechanics can be understood in its own terms, as a theory for reasoning about the physical world in the face of uncertainty. In this sense, unlike the Bohmians, Everettians, spontaneous collapseans, etc. they are not looking for a deeper theory of reality in order to understand quantum theory. This is what option 2 means and I would have thought that was completely clear.

It should also be noted that QBism is not the only neo-Copenhagen interpretation on the table. In my review article, I listed about a dozen of them. Therefore, option 2 needs to be phrased in such a way that it captures Zeilinger's views, Richard Healey's views, Copenhagenish versions of consistent histories, etc. It is a bit rich to back off on the wording of option 2 just because the QBists don't like it, as if they had a monopoly on neo-Copenhagenism. You are always going to miss some subtle details when you try to make a broad strokes characterization, but if the correct interpretation of quantum theory really does turn on such semantic issues then I despair of the whole enterprise.

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Alan M. Kadin wrote on May. 28, 2015 @ 20:32 GMT
Dear Dr. Merali,

Your article in Nature and your blog here provide a nice overview of the commonly discussed alternative interpretations of quantum mechanics. However, there is a simple, logically consistent alternative that no one (except me) seems to consider. Specifically, if an electron or a photon is a spatially extended field whose integrity is maintained by a nonlinear self-interaction, it can move as a soliton-like wave while following a quasi-classical particle-like trajectory. There is no indeterminacy, no cat superposition states, and no entanglement. Such a model predicts some experimental results quite different from orthodox QM. For example, the two-stage Stern-Gerlach experiment is used, by Feynman and others, as a paradigm for quantum measurement. In the alternative wave-dynamical model, rotation of the second magnetic polarizer will lead, not to a random dispersion of results due to Hilbert-space projection, but rather to a deterministic adiabatic rotation of the polarized state. This experiment has never actually been reported, although it should be straightforward using modern atomic beam apparatus.

For further information, please see my FQXi essay.

Thank you,

Alan Kadin

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FQXi Administrator Zeeya Merali wrote on May. 28, 2015 @ 20:34 GMT
Thanks Alan, I'll take a look at your essay.

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Jonathan J. Dickau wrote on May. 28, 2015 @ 21:32 GMT
It's good to see this Zeeya..

I greatly enjoyed this summary and following the threads given, both here and at Nature. Plus I think after reading the above, I need to look at Alan's essay too. I have always thought there was something more to the wavefunction than strict probabilists will admit, but seeing evidence that constrains the psi-epistemic view is heartening.

More later,

Jonathan

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Robert H McEachern wrote on May. 28, 2015 @ 22:26 GMT
Superpositions and wave functions are merely one way to interpret the Fourier Transforms at the heart of quantum theory. But another way to interpret them (as is common in communications theory) is as a tuned, parallel filter bank. When combined with "identical" particle/wave inputs and "magnitude detection", such a filter bank reduces to a histogrammer, which is why the whole procedure results in probability estimates - no superposition of wave functions required or desired.

Rob McEachern

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Georgina Woodward wrote on May. 28, 2015 @ 23:46 GMT
Thank you for this new article Zeeya. I also enjoyed reading your linked Nature article. I'd just like to address two quotes from that article "Quantum physics: What is really real?"

Quote: "Ever since they invented quantum theory in the early 1900s, explains Maroney, who is himself a physicist at the University of Oxford, UK, they have been talking about how strange it is — how it allows...

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Georgina Woodward replied on May. 29, 2015 @ 08:10 GMT
I should have said - Also the potential states are not independently fluctuating over time but are bound to the substantial object itself, which is the carrier. It's not quite correct to imagine the unique states existing or being an attribute the object prior to observation or measurement protocol. Take for example clockwise and anti clockwise spin. It is the rotation that is "bound to" the object but whether it is clockwise or anticlockwise depends upon how it is measured, the relationship to the apparatus or how it is observed, the relationship to the observer. I'm thinking that all of the possible outcomes are potential of the object, as it could be observed in many different ways but a particular state is only formed at measurement when the possibilities are constrained by the apparatus, measurement protocol or observer vantage point. Think of how many different ways the suspended beach ball might be observed prior to one observer stating its orientation.

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Thomas Howard Ray wrote on May. 29, 2015 @ 17:06 GMT
Zeeya,

First. let me thank you and congratulate you for staying dedicated to the deepest foundational issues. You never fail to bring focus to the big picture.

You got Shelly Goldstein to set it up perfectly right from the start. Indeed, what is left of physics, in a theory with so 'complacent' a view toward space and time?

"These axioms, which are about measurement and...

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Robert H McEachern replied on May. 29, 2015 @ 21:02 GMT
Tom,

The reason why axioms about measurement and observation cannot be derived solely "from something which doesn't refer to measurement or observation." is because sophisticated observers respond symbolically, rather than physically, to their physical inputs. Hence, knowing the physics about what is being observed, is not sufficient to determine how such observers will behave towards such observables.

Rob McEachern

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Thomas Howard Ray replied on May. 29, 2015 @ 23:25 GMT
Rob, that would be a a physical axiom then, wouldn't it?

"Axiom: Sophisticated observers possess absolute free will."

What is a sophisticated observer? What demarcates a sophisticated observer from an unsophisticated (i.e., unconscious) observer?

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Robert H McEachern replied on May. 30, 2015 @ 13:11 GMT
No free will or consciousness is required. A sophisticated observer is anything that can respond symbolically, rather than just physically. For example, a virus does that when it uses a DNA code. In different species, identical gene codes specify non-identical proteins to be produced.

Rob McEachern

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Georgina Woodward wrote on May. 29, 2015 @ 23:00 GMT
Identified states are product of relationships of observer to the source Object observed or likewise relationship of apparatus to the observed; that constrains the possible outcomes into one unique observable state.

A horizontal arrow (substantial object) is pointing both left and right as it may be viewed from either side. Only when observation is made is an emergent reality formed from...

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Georgina Woodward replied on May. 29, 2015 @ 23:04 GMT
Upon observation or measurement a limited sub set of total data is selected or a singular measure is made from which one unique state is the output (emergent )reality. This is a switch from considering all of the possibilities that might have been observed to considering only the one state output.If all of the possibilities were represented by a wave function the wave function representation...

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Georgina Woodward replied on May. 30, 2015 @ 04:50 GMT
Quantum experiment outcomes are probabilistic because starting states are unknown. And being unknown the state from all "viewpoints" is equally valid and likelihood of each state being detected can be given as a probability.

If a falling spinning coin is observed, filmed, from a particular viewpoint a starting state can be assigned to it from that viewpoint, and its non random motion over time can be used to calculate a certain (knowable) output state. Now without looking no starting state can be assigned as no singular viewpoint has been imposed. Even if the non random motion was precisely known the output could not be known with certainty without a starting state.

The output thus appears only to follow the rules of probability. This does not mean that the unseen reality is only probabilistic. The coin and associated states are evolving deterministically according to the coins momenta and effect of gravity (but for all potential viewpoints simultaneously.)

In order to have deterministic physics, rather than just probabilistic physics, occurring in the unseen reality all that is required is unseen objects obeying the deterministic laws of physics to which all of the possible states that might be observed can be assigned. Rather than just disembodied states in superposition in a mathematical space that only become real upon observation. The act of observation is forming a different kind of reality from the subset of data obtained. Which is a limited fixed state emergent reality. Rather than the absolute state of an unobserved object (at any scale) which is in all of the states that it could potentially be observed in, within the foundational Object reality.

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Steve Agnew wrote on May. 30, 2015 @ 19:25 GMT
Interpretation of a quantum wavefunction is a philosophical goal and is therefore not necessarily a physically realizable goal. There are no experiments that explain why the quantum universe is the way that it is…quantum is simply the way the universe is. Until science gets a quantum gravity, these kinds of interpretation issues will persist.

The fundamental problem is that mainstream...

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Steve Agnew replied on Jun. 6, 2015 @ 16:15 GMT
The question of wavefunction collapse appears to actually address the root of the two very different notions of quantum space and motion versus the relativity gravity notions of space and motion. The existence of objects in space and the motion of objects through space are very intuitive notions and largely due to our experience with gravity.

It is therefore useful to reframe wavefunction...

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Georgina Woodward wrote on May. 31, 2015 @ 01:41 GMT
At least part of the problem is not having acknowledged the relativity of measurement and perception at the very small scales of investigation . That the emergent reality post measurement can be a limited fixed state output relative to the orientation of the apparatus when actual measurement performed. The other possible states being relative to other orientations of observation not performed. So...

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Georgina Woodward replied on May. 31, 2015 @ 04:00 GMT
Another part of the problem is treating scenarios, the outcome of which do not depend on position of orientation of observation, in the same way as those that do. Whether a radioactive particle has decayed or not is not a matter of the relationship between object and observer (/apparatus), position or orientation. It is a change to the substantial source object itself.

This makes the Schrodinger cat analogy not representative of real superposition of states in founadational reality. That term superposition of states can be used to describe what exist in foundational reality, the potential of a source entity to give all possible observed outcomes eg having the potential to be observed as rotating clockwise and to be observed as rotating anticlockwise. The singular unique states do not exist alone unobserved but are formed by the measurement or observation .

The probabilistic nature of radioactive decay is not the same thing as the probabilistic outcomes obtained by measurement or observation alone of non radioactive entities. Outcomes that are one out of two or more possible 'viewpoint' states of an entity.

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Georgina Woodward replied on Jun. 1, 2015 @ 00:13 GMT
Quote, "Crudely speaking," says Fedrizzi, "in a psi-epistemic model the cat in the box is either alive or it's dead and we just don't know because the box is closed." But most psi-ontic models agree with the Copenhagen interpretation: until an observer opens the box and looks, the cat is both alive and dead." Quantum Physics:What is real? Zeeya Merali

If the analogy is flawed, in that the radioactive particle is not in a super position of states, of decayed and undecayed, then the analogy doesn't work to describe the Psi ontic viewpoints. The analogy has worked as intended to make them seem ridiculous but has also bamboozled everyone. Though my discussion may seem very naive I have tried to show how things can be in all states they may be found to have simultaneously so not arguing against super position of states itself as a concept.

Quote "Because radioactive decay is a quantum event, wrote Schrödinger, the rules of quantum theory state that, at the end of the hour, the wavefunction for the box's interior must be an equal mixture of live cat and dead cat".Quantum Physics:What is real? Zeeya Merali

This makes the assumption that all quantum events are of the same type. I would argue that the radioactive decay is not a simple change in situation of a quantum object. It is destruction of one object and creation of two new objects in foundational reality. The starting object (atom)and the two resulting objects (new atom and free particle) are not in a superposition of states. The new objects being different entities from the starting atom, that are also after the event two spatially separated objects. This is very different from a singular thing being all that it might be observed or measured to be. Such as the macroscopic examples given, or a non radioactive atom.

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Georgina Woodward wrote on Jun. 1, 2015 @ 00:53 GMT
Zeeya, All,

Quote "Another set of reality-based models, devised in the 1980s, tries to explain the strikingly different properties of small and large objects. "Why electrons and atoms can be in two different places at the same time, but tables, chairs, people and cats can't." says Angelo Bassi.... "Quantum Physics:What is real? Zeeya Merali

Can atoms and electrons be in two places "at the same time " or is this, as I suspect, a product of the mathematical description- which is about probability densities and not substantial entities? Imagine there is a lion and there are two watering holes in his territory. A probability density map for a hot midday might give two equally likely locations for the lion. However that does not mean the lion is in two places at once.Is that anything like what is going on? Some kind of maths trickery exacerbated by translation into English, perhaps also aided by the desire to seem mysterious.

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Georgina Woodward replied on Jun. 1, 2015 @ 02:31 GMT
Zeeya, All,

there does also seem to be the "no no" of not comparing like with like going on.

Probability densities could be used for effective, safe locomotion in a macroscopic environment if the visual sense was not available. I know that at meal times my table occupies three times as much space at other times, having large extendable leaves. I might say the probability density of large tables is highest at meal times and so at such times a much larger safety zone around the table is required. I might provide a bowl of cookies for young guests. I will then know without visual information that the probability density of youngsters is highest in the vicinity of the cookie bowl. Isn't it these kinds of considerations that should be compared with the quantum scenarios and not vision?

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Lawrence B Crowell wrote on Jun. 3, 2015 @ 19:45 GMT
The measure of a state being ψ-epistiemic is the overlaps between the so called hidden variable λ \in Λ(φ) for the state φ relative to the state ψ,

∫ _{Λ(φ)}μ_ψ(λ)dλ = Ω[φ, ψ] \langle φ |ψ\rangle^2

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Lawrence B Crowell replied on Jun. 3, 2015 @ 19:46 GMT
The measure of a state being ψ-epistiemic is the overlaps between the so called hidden variable λ \in Λ(φ) for the state φ relative to the state ψ,

∫ _{Λ(φ)}μ_ψ(λ)dλ = Ω [φ, ψ] \langle φ |ψ\rangle^2

\le ∫ μ_ψ(λ)ξ_m(φ|λ)dλ = |\langle ψ|φ \rangle|^2

under the measurement m. The overlap function Ω[φ, ψ] = 1 for a ψ-epistemic interpretation. ...

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John Brodix Merryman wrote on Jun. 5, 2015 @ 03:05 GMT
All we know is the past. All we are is the present.

All we know is form/information. All we are is energy.

Energy is conserved, thus it is always present. Conversely, energy is only present, so since it can never fall into the past, it is conserved.

Form manifests as a confluence of energy. Be it energies interacting, energy moving from source to receiver. The act of measurement involves using one form of energy to interact with another. So it should be no wonder observation is part of the creation of form/information.

Are quanta energy, or are they form? We can't measure energy, only its form, so how do we know?

If energy didn't have form, would it exist?

Could form be measured, without energy?

In order to be determined, doesn't an event first have to occur? Events are first in the present, then in the past. The laws may determine a particular outcome, but as there is no way know the total input into an event prior to its occurrence, than how can the outcome be deterministic?

All our knowledge is momentarily stabilized energy. It only seems deterministic due to the inertia. The only thing truly deterministic about the future is that it will happen, because the energy is conserved.

Someday this "quantum weirdness" will seem about as normal as a round earth and those who thought it strange simply had illusions the earth is flat.

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Georgina Woodward replied on Jun. 5, 2015 @ 04:27 GMT
Hi John,

good to see you back. You are the cheese to Lawrence's chalk : )

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John Brodix Merryman replied on Jun. 5, 2015 @ 13:05 GMT
Georgina,

Thanks. That's a good analogy. I keep trying to argue math is the skeleton, the shell, or calcium on the bottom of the pot, when everything else has been boiled away. Not some primal seed from which reality springs, as it seems mathology thinks of it as.

The ontic is the energy and the epistemic is the form. The irony is we want to think of the real as something solid and anything changing as ephemeral. There are reality based measurements, not a measurement based reality. Thus they are fuzzy, not just probabilisitic. Even a moving car doesn't have an exact location.

I didn't have the energy and motivation to argue it in the contest though, as the structure and discipline of knowledge mitigates toward a mathematical universe. Definition is static.

Currently nursing a broken collar bone, so my reality is being more static than usual.

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jim hughes wrote on Jun. 5, 2015 @ 19:55 GMT
How can we even talk about what 'exists', what's 'real' or what's 'physically out there', when words like 'exist' and 'physical' have no meaningful, non-circular definitions?

Ask someone what 'exist' means, and you'll probably elicit a slightly patronizing laugh. Persist, and you'll be offered something like 'it exists if it's there whether or not anyone observes it' which of course simply restates the question. It seems there's no possible reply that doesn't include some form of the verb 'to be'.

The meaning of 'physical' has been reduced to virtual emptiness. If pressed, we fall back in desperation to something like 'can't be further decomposed'.

These words are empty - there's nothing useful behind them. They seem to be placeholders for concepts we somehow wish we had.

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Robert H McEachern replied on Jun. 5, 2015 @ 22:00 GMT
"I think, therefore I am." Descartes could get no further, in demonstrating the existence of anything, without introducing new (unstated) assumptions.

Physics is not really about what "is", but about how things, that we can observe behave. But the only things we can directly observe are our own thoughts. So physics presupposes that there are things external to ourselves, that cause us to wonder how such things may behave, such that they induce us to think about them, as we do. The color of things, is a classic example. Things seem to behave, as if they have color. Things seem to behave, as if they have wave-functions. They have neither. But they behave as if they do, because the only behavior we can observe, is how we ourselves respond to them.

Rob McEachern

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John Brodix Merryman replied on Jun. 5, 2015 @ 22:36 GMT
Jim, Robert,

There definitely seems to be something, some reality, but with every effort to pin it down, "it' just slips away. Even our thoughts become a hall of mirrors, as each becomes an observation, enlargement, filter, diversion, etc. of the previous.

So currently there is this theory that it is only the mathematical formulae which model the patterns observed, that are the only true reality. Yet even that is a retreat into a formulaic subset.

All the patterns, structures, frames, contents, etc, seem subjective, relative and emergent, but emergent from what? Math? Isn't math a modeling of those patterns that are emergent in the first place?

If we were to go to the most elemental state, it would presumably be the equilibrium, where all that is emergent cancels out, when it isn't emerging. The void in which quantum energy fluctuates.

Then you have positive and negative, frequency and amplitude. It might seek to push out to infinity, but than fall back to the equilibrium. Basically energy in space.

What are color and sound? Acceleration and velocity? What is mass, but resistance and attraction?

All forms of energy.

Could it be the reason why there doesn't seem to be any there there, isn't the fault of what is there, but what we expect to be there? Our minds like static forms and images. Things we can see and measure and weigh and feel. That is what seems "real" to us. But there are lots of things that seem real to us, that we have come to realize are emergent from our interactions. Maybe we just have more layers to peel away.

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Akinbo Ojo replied on Jun. 6, 2015 @ 09:25 GMT
Provocative thoughts. The meaning of some things may be better discerned by thinking in the negative.

What does 'non-existence' mean? Does it have a meaningful, non-circular definition?

Is 'non-existence' there or not whether anyone observes it?

Can 'non-existence' be? Can it be further decomposed?

But the ultimate fundamental question is: Can what does not exist become existent, or the reverse, can what exists cease to exist?

Some aspects of our cosmology and quantum theories suggest that what exists can cease to exist, and what was non-existent can come to be existent (e.g. the universe).

Interesting things to contemplate...

In my opinion, the fundamental, sine qua non quality of what exists is the quality of being extended. I think Descartes and Leibniz support this.

Regards,

Akinbo

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Steve Agnew wrote on Jun. 6, 2015 @ 20:06 GMT
You have hit the nail on the head. There are certain notions in the universe in which we must simply believe, what I call axioms. These beliefs are necessary to anchor each of our consciousness's and allow us to predict the actions of objects.

jim hughes wrote on Jun. 5, 2015 @ 19:55 GMT, "How can we even talk about what 'exists', what's 'real' or what's 'physically out there',...

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John Brodix Merryman replied on Jun. 6, 2015 @ 23:42 GMT
Steve,

Think of reality as the dichotomy of energy and form. Form defines the energy and energy manifests the form.

Now consider our physiology. We have a central nervous system to process form, i.e., information and we have the digestive, respiratory and circulatory systems to process the energy that propels our intellectual processes.

So our perception focuses on the points of reference, the concepts, the terms, the mathematical symbols, the words, the descriptions, structures, definitions, delineations. Yet flowing through it all is that underlaying dynamic. Which is a dichotomy as well, with every action being balanced by all other actions and so there is that foundational circularity and in trying to put it all together we like to tie together all those points of reference, because that is what our mind sees. We don't see action, because it would just be a blur, we have reconstruct it from our digitized and quantified process of comprehension. In our very search for clarity, we miss the essence of energy powering reality out of the void.

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Anonymous replied on Jun. 7, 2015 @ 00:13 GMT
Well, you already know that I love axioms, especially the trimal of matter, time, and action.

Energy is of course of form of matter and so by mass-energy equivalence, they are one and the same. Form is a beast of space and therefore immediately suspect. I like time and action much more than form. We imagine form from sensations of time delays of objects and so your notion of form is very time like so you should call it time. Each point of reference, what I call landmarks, are just time delays that we sense.

Your underlying dynamic is clearly my action principle. Action is the integral of matter over time and closes the universe. You say that we do not see action and that is true. What we sense are time delays and changes for objects from which space and motion emerge.

As far as energy powering reality out of the void, I am a little less persuaded. For me, energy is matter and reality is matter, time, and action, so the void is something that simply emerges from matter, time, and action. There is really no void and the void is therefore a convenient placeholder both for things that we do not yet understand as well as for things that we will never understand.

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Anonymous replied on Jun. 7, 2015 @ 02:39 GMT
Steve,

I'm looking at it from the other side of the looking glass. I'm seeing matter as a "form" of energy.

When we study matter, it seems that under the form are complex interactions of energetic properties.



We think of quanta as particles but what is being described is a quantity of energy, like the amplitude of a wave. Consider other properties, like spin and charge, which are descriptions of energy. They seem to be associated with some underlaying entity, but what is it? A vortex has spin and polarity.

So what is this substance called matter? Presumably the Higgs gives mass, but what is described seems to be a spike of energy.

Yet it is our intuition that there must be some solid substance fronting this energy. Some particles in motion; Electrons, protons, neutrons, photons, quarks, bosons, fermions! Yet that seems to be where this issue of the indeterminacy of reality really comes in. All we can measure is their energy. While our intuition says, "There must be something there."

So until someone can point to something and say that is the irreducible particle of matter, I'm inclined to think of it as form expressed by energy.

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Rodney Bartlett wrote on Jun. 10, 2015 @ 10:02 GMT
Dear Dr. Merali,

Here's a comment i posted on Nature's website about your excellent article -

ay I propose an alternative to the probabilistic understanding of quantum mechanics - one using hidden variables which give exact predictions, in this case by the variables being base-2 mathematics (cosmologist Max Tegmark - director of FQXi, the Foundational Questions Institute which Zeeya...

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Rodney Bartlett wrote on Jun. 11, 2015 @ 09:23 GMT
PS to my previous comment yesterday -

The human-made universe (1) has all distance associated with its 1's and 0's deleted according to the Yale experiment (2), producing entanglement in space and in time - as well as a universe that is one qubit.

(1) "New way of developing information technology and imaginary time for the purpose of building the universe" (http://vixra.org/abs/1503.0169)

(2) "What is consciousness?" (http://vixra.org/abs/1502.0129)

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Than Tin wrote on Jun. 26, 2015 @ 18:00 GMT
Given that the conceptual foundation of Quantum Theory is the "wave-particle" duality; that in the Newtonian theory of classical physics, it is the "action-reaction"; that in Darwin’s theory of evolution, the "variation-selection"; that in Molecular Biology, the "gene-protein"; that in Philosophy, the "mind-body"; that in Cognition, the "analogy-reason"; and so on and on without one exception in all of our discourses, it would make sense to find out why dualities rule the world.

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William H. F. Christie wrote on Jul. 17, 2015 @ 23:54 GMT
In order to explain relativity, I came up with a rotating wave model of matter way back in 1979 and of course no one except some students and one Phd physicist were interested. Actually an editor of the Canadian Journal of Physics kindly wrote me and suggested a way to improve it which I did.

Quick and short of it is that relativity and QM are an inherent requirement of the rotating wave. It rotates and the only way to put it in motion is along the direction of its axis of spin.

Attached are brief (quick) diagrams and the full article which suggests how mass, along with electric charge is generated plus the real reason for gravity and expanding slowing universe (as far as we can see it).

In order to prove this axial spin in the direction of particle motion, my suggestion is to review the Stern Gerlach experiments (perhaps as Alan Kadin has suggested) and see if one can detect a polar cone which I refer to in the full article.

Another way is to review Dirac's spinors and equation and reconcile them with the rotational and translation velocities of the Rotating Wave. I don't see it as stepping back in time, but finding a different way to till the soil. It might then produce new technologies (EM propeller - massless rocket and rotating beacon transmitters).

Bill Christie

attachments: Rotating_Wave_-_Quick_View.pdf, Rotating_Wave_Wavicle_-_Full_Article.pdf

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Don Limuti wrote on Jan. 28, 2016 @ 22:00 GMT
Hi Zeeya,

What is really real....was really good. And the posts are excellent.

In my opinion the deBroglie-Bohm model is getting close, making it digital will get it even closer.

If you recall I am the author of an alternative theory that postulates that the motion of particles and energy is discontinuous on a continuous background of space-time (www.digitalwavetheory.com).

So, in addition to Many Worlds, Bohmian Mechanics and Collapse models the Nature article should include a Discontinuous Motion model of reality.



Thanks,

Don Limuti

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Gary Alan Gordon wrote on Mar. 22, 2016 @ 04:15 GMT
The question in the discussion is posed as whether or not it is true that "if there’s an objective reality, then the wavefunction is real". It is suggested here that this is perhaps not a useful question to ask. That would be the case if there is actually no objective reality. That is, if reality is always subjective, or in other words strictly relational and specifically real only relative to...

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Lorraine Ford replied on Mar. 22, 2016 @ 11:17 GMT
YES, the cat is an observer!

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Gary Alan Gordon replied on Mar. 22, 2016 @ 14:02 GMT
Yes, Lorraine, the observer need not be human. In fact, the observer need not be conscious or even alive. The observer can be any system that can respond to the events in question in any particular situation. The point of view here is that all reality is relative. And thus to the extent that reality is usefully represented in a particular case by a wavefunction, the wavefunction applies to that...

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alena lis wrote on Aug. 2, 2016 @ 09:13 GMT
Strictly speaking, physics investigates experience. The field of all experience is consciousness. Nature is, in essence, Consciousness.

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Gary Alan Gordon replied on Jul. 19, 2017 @ 14:55 GMT
alena - did you read the post just above yours? Why do you believe that consciousness is so essential? Did not our universe behave in a similar fashion before humans appeared on the scene? Are lower forms of life sufficient from a consciousness standpoint? Are even single-celled life forms conscious in some way? But what about a universe that does not contain life forms at all but does have the ability to respond to physical changes? Do such universes still behave lawfully in a way similar to our own? Your point of view appears to perhaps suffer from an excess of anthropomorphism.

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Georgina Woodward replied on Jul. 20, 2017 @ 01:19 GMT
Hi Gary. I am in agreement with you on the independence of material reality from conscious awareness of it. Measurement / observation creates a relation between observer and observed that can not exist without both parties.The representation produced from received information can not exist without the process involved in information acquisition and processing. Material reality however can exist without that process. Relative perception by an observer of the macroscopic World and quantum measurement bring about a new representation of reality. All relative measures, including direction of velocity and angular momentum require a viewpoint to be imposed. Without that viewpoint the relative measurements do not exist. In that sense the act of measurement /observation is bringing something new into existence that did not exist prior to establishment of the relation.

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Georgina Woodward replied on Jul. 20, 2017 @ 01:47 GMT
Orientation, direction and relative velocity/momentum are not independent of measurement /observation. Attributes such as seen colour and shape are also not independent, being produced by the observing system from received information. The colour seen does not relate only to the wavelength emitted from the object in question but other light in proximity from other objects and the illumination level. The shape seen is made from information received and not all information emitted from the object. The seen shape is therefore a limited representation of the entire object in material reality. The relative representation comes into being when it is produced and does not pre-exist unlike the source material reality. The representation of reality produced from information is not more real than the source reality that provides the information.

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Robert H McEachern wrote on Jul. 25, 2017 @ 11:45 GMT
Gary:

"If the other particle is then similarly measured, the result is not in general determined, but it has been shown to be mathematically correlated to the first one, as per Bell's results." The same is true of any classical system with a limited information content

Wavefunctions only exist as a mathematical technique for describing the behavior of observations. There is no real wave, wafting through the ether.

For further information: See this FQXi webpage and the pages it links to.

Rob McEachern

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Georgina Woodward replied on Jul. 26, 2017 @ 04:40 GMT
Robert, Gary,

It seems to me that some phenomena seem more suited to a wave description and so are easier to mentally reconcile with the wave function description. The likelihood of reflection of light from different thicknesses of glass surface does seem to be related to wavelength and how well the wavelengths fit into the distance. The double slit experiment might be understood as the wave effect of the vibration of an electron passing through both slits and then interfering and affecting the particle path rather than the particle passing through both. It can then be seen as an interaction with the environment that feeds-back rather than just an independent behaviour. It is, when viewed that way, a concrete interaction (rather than an abstract effect) that can work with the mathematics.

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Robert H McEachern replied on Jul. 26, 2017 @ 13:32 GMT
Georgina:

Wave *phenomenon* are the things best described as waves. For example, water waves are well described as waves. But that does not mean that the water IS a wave. Water consists of enormous numbers of water molecule particles. Water waves are merely the collective motions of those particles. The same is true in quantum *phenomenon*. There is no observable interference, when only a few particles have passed through the double slits. The interference pattern is built up from the collective distribution of the individual particle's collective behavior. Look at the these slides depicting different ways to interpret double slit interference and think about how interference patterns can be built up by particles scattering off non-smooth surfaces or fields.

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Georgina Woodward replied on Jul. 26, 2017 @ 20:59 GMT
Robert, the suggested medium does not provide electromagnetic information whereby the interference pattern could be seen and identified. I am proposing that nevertheless it can interact with electron entities and guide their paths. Such a medium is not a necessary part of Einstein's space-time and, as it provides no direct visual evidence of itself, it is not a part of the "Image reality" formed by observers. Yet the behaviour of the electron giving the results that are seen provides evidence of the interaction. I think the effect of an electron on the environment can be separated from the electron entity rather than considering the effect as the thing. (It seems to me that quantum field theory would have all effects and no causal thing.)

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Gary Alan Gordon wrote on Jul. 25, 2017 @ 17:30 GMT
Rob and Georgina,

I spoke loosely. By "real" I was not referring to ontic as opposed to epistemic. I personally believe that the wavefunction is strictly epistemic, so I would agree with you on that point. Furthermore, per relational quantum mechanics, I believe that the epistemic relevance of a given wavefunction applies to a specific observer of a subject system. It describes the state of the subject system before it is observed by the specific observer. And the state in this case is more properly viewed as depending on the knowledge available to the observer prior to the observation. It is interesting to consider cases where the wavefunction is impacted by knowledge that is available to the observer but not known to the observer. This can lead to unexpected results of the measurement. I am considering writing an article illustrating this result.

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Robert H McEachern replied on Jul. 25, 2017 @ 22:47 GMT
Gary:

"It describes the state of the subject system before it is observed by the specific observer." That is not possible, since the state being described is not even an attribute of the system being observed. Rather, it is an attribute of the observer-observed relationship. Hence, without the observer, there is no such state at all.

It is exactly the same as the classical case of "calling" a coin either heads or tails. The coin is neither, because it is always both - that is what a two-state superposition looks like, a two-sided coin. And that is why coins reproduce the so-called quantum correlations.

Rob McEachern

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Georgina Woodward replied on Jul. 26, 2017 @ 04:59 GMT
Robert I liked what you said about "coin calling ",I agree that the state described is an attribute of the observer-observed relationship. However I trust that when the method is complete but the result not yet collected the state is already a reality unobserved due to the relations between the atoms of the coin and table on which it rests. Those relations do not require an observer to form a mental picture to be actualised.

When the observer does form a perception of the product state that new model of reality supersedes the previous representation. The fixed state of the material coin-table interaction must precede receipt of information about it due to the non infinite speed of light. Information receipt by the observer is not feeding back to the material coin to make it match the perception.

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Robert H McEachern replied on Jul. 26, 2017 @ 13:15 GMT
Georgina:

The coin's state, is that it is in the state of being a coin - always - regardless of whether or not it is ever observed. And it always has two sides. The observer merely changes his or her *decision* about whether to observe it, from one angle or another. That has absolutely nothing to do with the physics of the coin per se. But it has everything to do, with the computation of so-called "quantum correlations." The exact same thing is true with regards to a photon's polarization or an electron's spin.

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Gary Alan Gordon wrote on Jul. 26, 2017 @ 18:28 GMT
Rob,

I have glanced at your linked references and it is immediately apparent that we are fellow travelers. I will respond more completely after I have studied your fascinating work. But my immediate response is that you should recognize that the unknown state of the coin in flight is strictly epistemic, not ontic. That is, the state is unknown before observation only because the potentially available information, (it's position, orientation and motion variable values) are not specified. I believe that the same is true for entangled linearly-polarized photons in a singlet state for example. Their polarization orientation is unknown, but the observed results are found to be correlated. There is no mystery to this. The unknown state of polarization is strictly epistemic, not ontic. The observed results are correlated because the polarization states, while unknown for the two photons are always in opposite directions in the same orientation. The whole business about the state of the "first" photon collapsing when it is observed, and this collapse instantaneously changing the state of the other photon is just so much nonsense. (For one thing, if they are spatially separated, there is no absolute "first" one to be observed.)

I will be amazed if you disagree with any of this!

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Robert H McEachern replied on Jul. 26, 2017 @ 20:05 GMT
I do not disagree. But I would point out a subtlety that you (and you are hardly alone in this) have overlooked. The state being looked for, is not merely unknown, it is non existent, outside of the imaginations of those that are wasting their time, trying to observe and interpret it. It is no more real than Percival Lowell's Martian canals. The sad part is, Bernard d'Espagnat came within a heartbeat of recognizing this, forty years ago - but then it was lost.

Rob McEachern

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Gary Alan Gordon replied on Jul. 26, 2017 @ 21:41 GMT
Rob,

When you say that the state is non-existent, you probably are referring to the QM state, which describes the photon as having a random polarization. I agree with that assessment, but when I say that the photon has a state, I am referring to a determined state, not a random QM type state. Once the 2 photons are emitted in their singlet state, they have some definite polarization which happens to be unknown but not random. This is no less a state then the initial state of a classical particle defined by its position and velocity in some force field. Perhaps QM states should be given some other name.

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Robert H McEachern replied on Jul. 27, 2017 @ 00:26 GMT
I was referring to the fact that the unknown state, only has a single component. The second component, whose measurement is the entire reason for ever performing a Bell test in the first place, does not exist. Hence the strange correlations.

Rob McEachern

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Gary Alan Gordon wrote on Jul. 26, 2017 @ 18:48 GMT
Rob and Georgina,

I must add that I believe that there are some other QM phenomena that appear to be truly ontic rather than epistemic. As one example, consider single photon interference at the output of a two path beam-split and recombine apparatus. Results show that as one of the two paths is slowly lengthened, the interference result changes as one would expect for two waves traveling down the two paths. But there is only one photon in the apparatus at a time, not two! And we know that a photon cannot split and go both ways. So it is really the fact that the photon could have gone either way that appears to produce the interference pattern in this case, a true ontic QM effect. IF some means with "negligible impact" is introduced to detect which path is taken by the photon, the interference pattern no longer appears. A loop can be introduced into one of the paths so that it can be much longer than the other path, and there will still be an interference pattern, as long as we don't know when the photon was emitted from the source. If we introduce a "negligible impact" measurement to determine the instant of emission, the interference pattern disappears. This seems to introduce an epistemic element to these phenomena in some way. Some food for thought.

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Robert H McEachern replied on Jul. 26, 2017 @ 20:17 GMT
The interference pattern is almost entirely due to the information content of the apparatus geometry, not the properties or information content of the entities passing through that geometry. Consequently, if you change the geometry (as one of the two paths is slowly lengthened), the pattern, caused by that geometry, will change.

Do you suppose that the scattering pattern, produced by your mother's face, which enables you to recognize her face by sight, is being caused by some mysterious property of solar photons? Of course not. It is caused almost entirely by the scattering geometry. So are the interference patterns.

Rob McEachern

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Gary Alan Gordon replied on Jul. 26, 2017 @ 22:20 GMT
Rob,

I don't follow that argument. Nothing is recorded by the apparatus until a photon passes through it and is detected with some strength. The recorded strength varies in the way that one would expect due to interference of two waveforms at the same frequency. How is the information content of the apparatus defined? How does that information content influence the recorded signal strength? The apparatus does not involve scattering of the photon in any way. The photon passes through a half silvered mirror to two paths and are eventually recombined and directed to the detector. And remember that there is only one photon involved at a time. I don't recognize anybody's face with one photon.

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Robert H McEachern replied on Jul. 27, 2017 @ 00:17 GMT
Having two paths, rather than one, for the photon, is like having two planets, rather than one, in the vicinity of a rocket's trajectory. The mere existence of a second planet causes the force field near the rocket, to differ from what it would be if there were only a single planet. That difference in field, causes the rocket to scatter into a different path. The mere existence of another path *is* scattering.

Have you ever seen a mirage? That is scattering caused by the changing temperature and density fields, that the light is passing through. If the field exhibits rippled "interference" patterns, then so will any photons scattering through those fields. The number of photons is irrelevant. If the field changes the energy of the particle, then the recorded strength will vary.

The interference thus really exists. But it exists as the particle scattering properties of the field through which the particle passes, not as a propagating wave phenomenon. It is analogous to particle trajectories being altered, by the warping of spacetime, caused by the existence of masses, in General Relativity.

Rob McEachern

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