What a timely article and comment. I've been watching a lecture series over the last few days about quantum mechanics and the many worlds interpretation. And I have questions.
I may have missed it or didn't understand it when I heard it explained. What underpins the notion that when a particle transitions from a superposed to defined state, the other basis states continue to exist? If they have to continue to exist, then okay many worlds, but why do we think (or know?) they must continue to exist?
3Blue1Brown has a very good explanation of how light works as a wave
And the barber pole effect shows how matter (sugar) rotates light
https://www.youtube.com/watch?v=QCX62YJCmGk
There is also evidence that "photons" are just thresholds in the material that is used to detect light. The atoms vibrate with the EM-wave and at a certain threshold they switch to a higher vibration state that can release an electron.
If the starting state is random, the release of an electron will often coincide with the light that is transmitted from just one atom.
This threshold means that one "photon" can cause zero or multiple detections. This was tested by Eric Reiter in many experiments and he saw that this variation indeed happens. Especially when the experiment is tuned to reveal this. By using high frequency light for example. It happens also in experiments done by others, but they disregarded the zero or multiple detections as noise. I think the double detection effect was discovered when he worked in the laboratory with ultraviolet light.
There's no problem reconciling the quantum with the Newtonian. Quantum mechanics recovers Newtonian mechanics in the appropriate limit. The problem is reconciling the quantum and the Einsteinian.
Actually, Newtonian gravity can be added to QM and work perfectly well. It's GR gravity that doesn't work with QM, especially if you try to model very high curvature like you'd get near a black hole.
Quantum Electro-Dynamics (QED) is the application of Special Relativity (non-accelerating frames of reference, i.e. moving at a constant speed) to Electromagnetism. Thus, the issue is with applying accelerating frames of reference (the General in GR) to QM.
I think neither analogy is correct. We're using macro metaphors (real world things at human time and spatial scales) to explain microscopic phenomena that may not correspond to anything that we find familiar.
I agree with this. As a physicist, I believe the most accurate resolution is to say that «quantum fields» and «quantum particles» describe neither waves (in the sense of e.g. water or acoustic waves) nor particles (in the sense of marbles and billiard balls), but a third thing that simply has some things in common with both classical waves and classical particles. The analogies are useful for understanding that third thing, but if you believe the analogies too literally, then you’ll make mistakes.
One has to wonder how far can emergence stretch given enough time, some kind of entropic limit probably exists but I'm just a layman, hopefully someone more knowledgeable can share if we already know a physical hard limit for emergence.
If we take a simple definition of technology - such as “tool” or some external inanimate thing we use as an extension of ourselves - then I think all animals on Earth that we have deemed intelligent to some degree use “technology”. Crows using sticks to pick things out holes, chimps crafting spears for hunting, dolphins wearing “hats”, octopuses building stone fortresses, etc. So I guess it’s important to define the limit of the definition of technology.
Another interpretation of the double-slit posits a guiding 'Pilot Wave' separate from physical particles... aka DeBroglie-Bohm Theory or Bohmian Mechanics.
Apparently it's not popular among professional physicsts though John Bell investigated it a bit. Einstein had some unpublished notes in the 1920s about a "Gespensterfeld" (ghost field) that guided particles.
Born was influenced by this 'Ghost field' idea when he published his famous interpretation of the 'Wave Function' |Ψ|^2 as a probability rather than a physical field.
The way I've always thought of this is there are potentials for interactions and interactions.
Interactions act like point particles and potentials for interactions act like waves.
Arguing over the distinction is a bit like debating whether people are the things they do, or the thing that does things. There is some philosophical discussion to be had, but for the most part it doesn't really matter.
It still interferes with itself, and that interference affects the pattern of detections. It's as if the photon were a wave right up until the moment of detection, at which points it's forced to “particalize” and pick a spot to be located at — but it's the amplitude of the wave it was just before detection that determines where on the detection screen the photon is likely to show up. If you send many photons through one at a time, the detections (each just a point on the screen) will fill out the expected double slit pattern.
I've always wondered what degree of confidence exists amongst the cogniscenti that a single photon event happened. I tend to think the criteria of measurement here would suggest the most likely outcome was a shitload more than 1 photon, and that all the "but we measured we can see one only" measurements are themselvs hedged by a bunch of belief.
That said, I do like the single photon experiment, when it's more than a thought experiment.
Double slit experiment has been done with electrons which are, afaik, much easier to detect and send single file. It's been done with molecules. It's not a thought experiment.
Quantum superposition is real. There's no doubt about that.
It's a wave of probability, that interferes through the slits and then collapses into a probability of one somewhere along the wavefront at the point of detection. Whatever that means :-)
As the other comments have already mentioned, it interferes with itself, so you still observe the same interference patterns [0] [1]. Which admittedly seems impossible at first, but so does the rest of quantum physics.
Depends on the definition of miracle I guess. There's all sort of unintuitive shit going on in the quantum world, but we can make it happen so reliably that it's hardly a miracle anymore. Wikipedia defines a miracle as "an event that is inexplicable by natural or scientific laws and accordingly gets attributed to some supernatural or praeternatural cause". But we understand "how" quantum mechanics quite well, even if the behavior described by the equations is not very intuitive to humans.
> To quantify this influence, the team applied their model to Terbium Gallium Garnet (TGG), a crystal widely used to measure the Faraday effect. They found that the magnetic field of light accounts for about 17% of the observed rotation at visible wavelengths and up to 70% in the infrared range.
Nearly 20% seems already significant, but 70%?! that's massive.
This isnt exactly new. This is a obvious and predicted effect of ECE Theor. I'm surprised that neither the article nor any other commentor mentioned it yet.
tl;dr on ECE Theory: Gravity is a curvature of spacetime, electromagnetism is a torsion.
Einstein–Cartan–Evans theory or ECE theory was an attempted unified theory of physics proposed by the Welsh chemist and physicist Myron Wyn Evans ..., which claimed to unify general relativity, quantum mechanics and electromagnetism. The hypothesis was largely published ... between 2003 and 2005. Several of Evans's central claims were later shown to be mathematically incorrect and, in 2008, the new editor of Foundations of Physics, Nobel laureate Gerard't Hooft, published an editorial note effectively retracting the journal's support for the hypothesis.
We intuitively think in particles and see a world of billiard balls colliding with one another.
But actually everything is merely waves and fields.
There's going to be a time where humans finally reconcile the quantum with the newtonian -- and I can't wait for that day
What a timely article and comment. I've been watching a lecture series over the last few days about quantum mechanics and the many worlds interpretation. And I have questions.
I may have missed it or didn't understand it when I heard it explained. What underpins the notion that when a particle transitions from a superposed to defined state, the other basis states continue to exist? If they have to continue to exist, then okay many worlds, but why do we think (or know?) they must continue to exist?
3Blue1Brown has a very good explanation of how light works as a wave And the barber pole effect shows how matter (sugar) rotates light https://www.youtube.com/watch?v=QCX62YJCmGk
There is also evidence that "photons" are just thresholds in the material that is used to detect light. The atoms vibrate with the EM-wave and at a certain threshold they switch to a higher vibration state that can release an electron. If the starting state is random, the release of an electron will often coincide with the light that is transmitted from just one atom.
This threshold means that one "photon" can cause zero or multiple detections. This was tested by Eric Reiter in many experiments and he saw that this variation indeed happens. Especially when the experiment is tuned to reveal this. By using high frequency light for example. It happens also in experiments done by others, but they disregarded the zero or multiple detections as noise. I think the double detection effect was discovered when he worked in the laboratory with ultraviolet light.
Here is a paper about Eric Reiter's work: https://progress-in-physics.com/2014/PP-37-06.PDF And here is his book. https://drive.google.com/file/d/1BlY5IeTNdu1X6pRA5dnJvRq3ip6...
There's no problem reconciling the quantum with the Newtonian. Quantum mechanics recovers Newtonian mechanics in the appropriate limit. The problem is reconciling the quantum and the Einsteinian.
But there’s no quantum explanation of gravity, right?
Actually, Newtonian gravity can be added to QM and work perfectly well. It's GR gravity that doesn't work with QM, especially if you try to model very high curvature like you'd get near a black hole.
Quantum Electro-Dynamics (QED) is the application of Special Relativity (non-accelerating frames of reference, i.e. moving at a constant speed) to Electromagnetism. Thus, the issue is with applying accelerating frames of reference (the General in GR) to QM.
At this point we have several
They’re all largely untestable though
String theory, LQG, half a dozen others
There’s no explanation of gravity, quantum or no. There are merely descriptions.
Isn't everything descriptions, in the end, aka models? Turtles all the way down...
Classified
I think neither analogy is correct. We're using macro metaphors (real world things at human time and spatial scales) to explain microscopic phenomena that may not correspond to anything that we find familiar.
I agree with this. As a physicist, I believe the most accurate resolution is to say that «quantum fields» and «quantum particles» describe neither waves (in the sense of e.g. water or acoustic waves) nor particles (in the sense of marbles and billiard balls), but a third thing that simply has some things in common with both classical waves and classical particles. The analogies are useful for understanding that third thing, but if you believe the analogies too literally, then you’ll make mistakes.
Thank you! That's a paradigm that I had in the back of my head, but not explicitly phrased.
Photons aren't like particles nor waves. Particles and waves are like photons. And, as with all similes, they fail when you inspect too closely.
That we're just collections of wave interference is wild.
We're built on so many layers of emergence, it's wild!
quantum particles => atoms => chemistry => biochemistry => cellular life => multi-cellular life => intelligence
It can keep going!
Intelligence -> societies -> technology -> ?
One has to wonder how far can emergence stretch given enough time, some kind of entropic limit probably exists but I'm just a layman, hopefully someone more knowledgeable can share if we already know a physical hard limit for emergence.
I like your progression. It makes me wonder if intelligence could lead to technology absent societies.
If we take a simple definition of technology - such as “tool” or some external inanimate thing we use as an extension of ourselves - then I think all animals on Earth that we have deemed intelligent to some degree use “technology”. Crows using sticks to pick things out holes, chimps crafting spears for hunting, dolphins wearing “hats”, octopuses building stone fortresses, etc. So I guess it’s important to define the limit of the definition of technology.
Just listen to Feynmann trying to explain why he can't explain magnetism in macro terms (e.g. https://www.youtube.com/watch?v=MO0r930Sn_8)
So, are you telling me that we actually-don’t- know how magnets work lol?
Not at all - but we don't know how to explain how they work using any analogy from the macro world that we intuitively understand.
I don't have the math, but doesn't quantum field theory say this?
Maybe think of it as binary(particles) vs analog(waves).
> But actually everything is merely waves and fields.
The two-slit experiment says otherwise.
Another interpretation of the double-slit posits a guiding 'Pilot Wave' separate from physical particles... aka DeBroglie-Bohm Theory or Bohmian Mechanics.
Apparently it's not popular among professional physicsts though John Bell investigated it a bit. Einstein had some unpublished notes in the 1920s about a "Gespensterfeld" (ghost field) that guided particles.
Born was influenced by this 'Ghost field' idea when he published his famous interpretation of the 'Wave Function' |Ψ|^2 as a probability rather than a physical field.
More info: Nonlocal and local ghost fields in quantum correlations. https://arxiv.org/abs/quant-ph/9502017
Veritasium did a video on this [1] with a surface of oil to replicate the effect on a petri dish.
[1] https://www.youtube.com/watch?v=WIyTZDHuarQ
Pilot wave is still my favorite - I don’t really believe it, but I like the image
It is indeed a great way to translate classical intuitions to the quantum domain.
It does not. It shows that individual photons self interfere, so they cannot be idealized particles.
The way I've always thought of this is there are potentials for interactions and interactions.
Interactions act like point particles and potentials for interactions act like waves.
Arguing over the distinction is a bit like debating whether people are the things they do, or the thing that does things. There is some philosophical discussion to be had, but for the most part it doesn't really matter.
Are you getting confused with the photoelectric effect experiment?
Hmm? The double slit experiment definitely shows that particles are waves—weird quantum waves, but still waves.
The two-slit experiment shows that photons behave like waves if you aren't looking at them, and that they fail to behave like waves if you are.
Everett reconciled that. They only appear to fail to behave like waves because the observer is waves as well.
what happens when you only send a single photon down the line though?
It still interferes with itself, and that interference affects the pattern of detections. It's as if the photon were a wave right up until the moment of detection, at which points it's forced to “particalize” and pick a spot to be located at — but it's the amplitude of the wave it was just before detection that determines where on the detection screen the photon is likely to show up. If you send many photons through one at a time, the detections (each just a point on the screen) will fill out the expected double slit pattern.
It's worth reading about, but it's kind of wave-like even then: https://en.wikipedia.org/wiki/Double-slit_experiment#Interfe...
It would be going too far to say it's only a wave though. It's both wave and particle.
The way I read GGP was as contradicting the assertion that everything is just waves and not at all particles.
I've always wondered what degree of confidence exists amongst the cogniscenti that a single photon event happened. I tend to think the criteria of measurement here would suggest the most likely outcome was a shitload more than 1 photon, and that all the "but we measured we can see one only" measurements are themselvs hedged by a bunch of belief.
That said, I do like the single photon experiment, when it's more than a thought experiment.
Double slit experiment has been done with electrons which are, afaik, much easier to detect and send single file. It's been done with molecules. It's not a thought experiment.
Quantum superposition is real. There's no doubt about that.
It's a wave of probability, that interferes through the slits and then collapses into a probability of one somewhere along the wavefront at the point of detection. Whatever that means :-)
As the other comments have already mentioned, it interferes with itself, so you still observe the same interference patterns [0] [1]. Which admittedly seems impossible at first, but so does the rest of quantum physics.
[0]: https://www.feynmanlectures.caltech.edu/III_01.html#Ch1-S5
[1]: https://en.wikipedia.org/wiki/Wave%E2%80%93particle_duality#...
> Which admittedly seems impossible at first, but so does the rest of quantum physics.
AKA, miracles can happen, hehe.
I'm not trolling, this is a philosophical point I'm making.
Depends on the definition of miracle I guess. There's all sort of unintuitive shit going on in the quantum world, but we can make it happen so reliably that it's hardly a miracle anymore. Wikipedia defines a miracle as "an event that is inexplicable by natural or scientific laws and accordingly gets attributed to some supernatural or praeternatural cause". But we understand "how" quantum mechanics quite well, even if the behavior described by the equations is not very intuitive to humans.
do it once, it looks like one particle.
repeat the single photon launch many times, and you see a wavelike distribution of photon strikes
> To quantify this influence, the team applied their model to Terbium Gallium Garnet (TGG), a crystal widely used to measure the Faraday effect. They found that the magnetic field of light accounts for about 17% of the observed rotation at visible wavelengths and up to 70% in the infrared range.
Nearly 20% seems already significant, but 70%?! that's massive.
Seems to be a minor typo . Paper:
>17.5% of the measured value for Terbium-Gallium-Garnet (TGG) at 800 nm, and up to 75% at 1.3 µm.
Here's what the crystal looks like
https://www.photonchinaa.com/tgg-terbium-gallium-garnet/
Here's transmission plot (UV-IR)
https://www.samaterials.com/terbium-gallium-garnet-crystal.h...
Note there's almost no effect on transmission
Relevant? https://dspace.mit.edu/handle/1721.1/51819
Nice to see a graph of % magnetic priportion and log wavelength going from radio to gamma.
How did no one notice that before, and what else have they (we) missed?
If I'd to guess: all that exp. characterization to-date has revealed no anomaly (See my other comment)
This team might have looked at bandstructure. or not (they didn't say, & I'd guess not)
Obviously hindsight is 20/20 but this sentiment just reeks with comical levels of hubris
> However, the new research demonstrates that the magnetic field of light, long thought irrelevant,
so what exciting applications can we see from this?
We will put a box containing a little light and a magnet into every home and people will lose their goddamned minds looking at it every day
[flagged]
People in countries you don't like can still do valid science.
This isnt exactly new. This is a obvious and predicted effect of ECE Theor. I'm surprised that neither the article nor any other commentor mentioned it yet.
tl;dr on ECE Theory: Gravity is a curvature of spacetime, electromagnetism is a torsion.
From Wikipedia:
Einstein–Cartan–Evans theory or ECE theory was an attempted unified theory of physics proposed by the Welsh chemist and physicist Myron Wyn Evans ..., which claimed to unify general relativity, quantum mechanics and electromagnetism. The hypothesis was largely published ... between 2003 and 2005. Several of Evans's central claims were later shown to be mathematically incorrect and, in 2008, the new editor of Foundations of Physics, Nobel laureate Gerard't Hooft, published an editorial note effectively retracting the journal's support for the hypothesis.
But do they understand how magnets work?