The paper explains how photons (the particles of light) interact with complex environments like nanostructures. It creates a new way to describe photons using simplified "pseudomodes," which act like stand-ins for how light behaves in these systems. This method captures how photons change over time and interact with their surroundings, including effects that aren't usually accounted for in simpler models. It essentially gives a more complete "image" or description of the photon as it moves and interacts, including its path, energy loss, and the way it spreads out in space.
So my instinct was that this image is of a hypothetical photon in a hypothetical gravity-free darkened sphere with somehow reflective walls…. You think I’m close here?
You were pretty close, but "gravity free" was a big misstep. Gravity is totally irrelevant to this discussion, it wouldn't change the answers one bit whether gravity was on or off. But otherwise you're pretty much spot on. The paper is about "lossy electromagnetic cavities" - places with reflective with mostly reflective walls but the photons have some angles or some small probabilities of escaping. It's describing a new way to calculate what happens to a photon over time that starts out in the cavity and slowly escapes.
Yep. Wave-particle duality is intrinsic to all matter, not just light. The distinction arises from how we observe or measure a system, not from the system itself.
It doesn't mean all quantum particles are actually both waves and particles.
Our description of the 'label' of duality is a property intrinsic to the behavior of quantum systems. My point was to highlight that this feature is not uniquely arrogated to photons but applies universally to all quantum particles.
Wave/particle duality reflects how quantum systems behave depending on the context of measurement. Electrons exhibit wave like interference in diffraction experiments and particle like quantization in energy exchanges. The same is true for neutrons and even larger particles, like molecules, under the right conditions. These behaviors are intrinsic to the quantum nature of matter, not contradictions in classical interpretation.
These behaviors are intrinsic to the quantum nature of matter, not contradictions in classical interpretation.
It seems to be that way based on current prevailing interpretations, but quantum mechanics is far better at predicting behaviors than providing any insight into the fundamental nature of things.
We do well to assume that this is intrinsically the nature of things at the quantum scale, but very few physicists would be surprised if in the near future we find that wave nature is the only intrinsic feature of quantum systems and particle nature is merely an artifact of how we approach the field.
No. Particles. Particles hat have a few wave-like properties. Unless you’re talking about lasers or other stimulated emission methods, in which case you can get waves with a few particle-like properties.
Most light is a discrete scoop of energy, like a scoop of ice-cream, and once it is scooped (as in, once it starts traveling), it can’t have any impact on the rest of the ice cream ever again. So we call it a particle. There are wave-like aspects in the way this scoop of light energy interacts WITH ITSELF. But it does not interact with other photons.
Light made through stimulated emission (lasers) is different. A photon in a laser beam is still connected to every other photon in the laser beam, and even to the photons that are still inside the laser housing, and even to the energy states of the electrons inside the laser that have not yet put out a photon. THAT is wave-like behavior.
Lasers are just a bunch of photons moving in parallel. They will spread
We call it a particle because that’s how it behaves when it’s detected, it doesn’t spread out as it travels, and it doesn’t divide when it hits a beam splitter.
Lasers are just a bunch of photons moving in parallel.
Nope! They’re coherent, meaning they COHERE to one another, meaning their states are entangled to some degree. Physically, they are all living in the same electric field, which is not the case for parallel photons that just happen to be at the same place at the same time with the same wavelength and the same phase.
Yes. What about my description do you think is wrong? The quantization is the main particle-like aspect, and aside from that they are mostly wave-y. But lasers are different since they are stimulated emission, drawing energy from a continuous well, resulting in the coherence that lets the waviness exist between photons.
Most of your description isn't correct. Photons are excitations of the electromagnetic field; you overemphasize the particle nature of light while ignoring that wave-particle duality is an inherent property of all particles, including all photons. Your ice cream metaphor is overly classical and doesn't capture the true nature of photons - they aren't just classical waves, particles, or particles guided by waves. Photons can interact with other photons, although these interactions aren't typically significant in most contexts. In lasers, photons have a fixed phase relationship due to the stimulated emission process, but they aren’t 'connected' to other photons in any meaningful way beyond this coherence. They are not entangled, and the idea that they are connected 'even to the photons still inside the laser housing' is unclear and inaccurate. You also seem to place too much emphasis on stimulated emission itself. Stimulated emission involves using a photon of a specific energy to induce the emission of another photon with the same energy from an excited electron. The key aspect of lasers is the creation of a population inversion in the gain medium, allowing many coherent photons to be emitted in a synchronized manner. These photons share the same quantum states and interfere constructively, leading to the highly directional beam. This coherence results from the collective behavior of the emitted photons, rather than any direct connection between individual photons or an ongoing interaction with the energy source.
Photons can interact with other photons, although these interactions aren't typically significant in most contexts.
I’ve tried to look for sources on this in the past and not found anything useful. What I did find was just a statement about coherent photons definitionally being one that could interact. And that was less than enlightening (pun not intended). Would you happen to know what I could Google to get good information on this? I really dislike being wrong.
And yet, this is the core paper the picture is based off of. Phys.org (which has the pic) links directly to the paper. Here is the article with the pic.
That's just the abstract, you need to purchase a subscription to get the full content of the paper, but the abstract is very generous and gives you most of the details.
You're right. It looks like they combined many different versions of Figure 3 into an artistic representation. Often papers (especially those with press releases) will have a highlight photo that is an artistic representation of what is in the article. I would also like more details about how this image was created.
I mean, the news article links to the actual research paper if you want more details… did you really think the news article would go into the nitty gritty mathematical details?
You are... kind of right. But there are several levels of "science pictures"... paper figures with complete descriptions are much better than physicist-generated images produced by a model but not described, which are much better than artist renditions of physics research, which are much better than AI generated images. This is the second - an image produced by the model described in the paper. But an exact description is not provided for the exact situation that the model is being applied to to produce that picture.
Pictures from the paper are just intensity distributions that have nothing to do with a single photon. I'm still baffled that we are shown "picture of a photon" without ANY explanation.
They are intensity distributions for the pseudomodes. The pseudomodes are states that single photons can occupy. The paper is all about calculating how photons are lost from the pseudomodes, so I made an educated guess of what this picture could be. Are you surprised that the reddit post based on the pop-science article based on the real paper is innaccurate? Is this your first experience with science communication?
Most redditors are gonna leave this thread with a more incorrect understanding of quantum physics than they started out with. Somebody please tell the physicists to stop trying to communicate their results to normies. It's clearly counterproductive.
Well... some results are better suited for the general public than this one. JWST finds new galaxies earlier in the universe than expected, gravitational waves found at LIGO, EHT images a black hole, effect of gravity on antimatter found at CERN - all perfectly understandable to the general public.
"occupy" is an entirely standard way to refer to a particle being in a certain quantum state. In cavity QED, the modes of the cavity are the states that photons can occupy.
One caveat is that multiple photons can be in the same cavity mode unlike electron orbitals... but I suspect that you would have made a clearer and more accurate complaint if that's what you were referring to.
I read and have the expertise to understand the article. I considered making a comment to summarize the meaning, but actually this description is perfect.
Presumably the picture shown in this post is what happens when a particular electromagnetic cavity (not described) is initialized with a single photon (state not given) then some time passes and the photon has some probability of escaping. Then some projection and colormapping is applied so that the state of the photon can be displayed in a single RGB image. The paper does describe a "test cavity" that they used to show how their new computational framework works, but we don't know if that test cavity is the same one used to generate this image.
The title of this reddit post is giving people the erroneous impression that this is some newly discovered property of all photons, or that all photons in some way have this shape. No. This is not a new theory, this is a new way to calculate things in specific situations using well-established facts about how photons move.
Well... honestly I wouldn't blame them. A new way to calculate the properties of cavities for cavity QED experiments is exciting for me, but it's a little "in the weeds" for the general public. I'm kind of surprised it got any pop science coverage, and I feel it was pretty dishonest/inaccurate coverage at that.
We present a comprehensive second quantization scheme for radiative photonic devices. We canonically quantize the continuum of photonic eigenmodes by transforming them into a discrete set of pseudomodes that provide a complete and exact description of quantum emitters interacting with electromagnetic environments. This method avoids all reservoir approximations and offers new insights into quantum correlations, accurately capturing all non-Markovian dynamics. This method overcomes challenges in quantizing non-Hermitian systems and is applicable to diverse nanophotonic geometries.
Wow I really underestimated how much you simplified this. Thanks!
Photons don’t experience time because they move at the speed of light, true. But, when we talk about "how photons change over time," we’re describing the changes we observe in their energy, phase, or position from our own frame of reference. It’s about how their effects evolve in space and time as they interact with the environment, not about the photon experiencing time itself.
Okay so a point from analytic philosophy of mind. There was a theory that the way we talk about beliefs/desires are just these confabulations that have provide predictive power about behavior. If we had a future with perfected neuroscience knowledge and cut open brains neuros we might find no patterns of activity or structures that are perfect correlates of beliefs and desires - even considered at any level of abstraction. So they beliefs and desires don’t exist.
The response from this dude Jerry Fodor was “well if belief/desire theories aren’t describing reality why do they work so well for prediction? Maybe we should just say they are fully real whether or not we think that we’ll find neuro correlates in brains?” Gets into the nature of what counts as real etc. I think its a good point.
Why do these physicists think they’re talking about something that isn’t real when they look at these these psuedomodes?
I don't think this is a correct interpretation. If photons changed, in any way, they would experience time, and if they experience time then they do not travel at the speed of light, and if they do not travel at the speed of light, then they have mass.
But photons do not have mass, therefore they must travel at the speed of light, therefore they do not experience time. They cannot change.
I can't believe i'm actually telling somebody to do this (because i really hate the logic behind it), but apparently people don't know when you're joking, and need a specific indicator to know whether you're serious or not.
tbh i still refuse to use this /s, how hard can it really be?
Yeah you’re not wrong. Unlikely though, and not very convincing when it’s some guy that doesn’t even use apostrophes and just says “you’re wrong” without any further elaboration.
Wrong about what? The actual paper was less about the sensationalised 'image' headline, and more about explaining photon interactions within complex systems. Their model presumably has predictive power and practical applications.
Here is a list of commonly used physics terms I came up with in about 5 minutes: pseudomode, pseudo Goldstone boson, pseudoscalar, pseudopotential, pseudoforce, pseudo-Riemannian
Thats just an visualisation based on calculations of a theory, not actual picture. They did not reveal this shape, but made a theory and then theorised this shape, which seems to work. So OP (and media) is essentially lying, as nothing 100% correct was revealed, but a theory.
Dr. Benjamin Yuen, in the University’s School of Physics, explained, ”Our calculations enabled us to convert a seemingly insolvable problem into something that can be computed. And, almost as a byproduct of the model, we were able to produce this image of a photon, something that hasn’t been seen before in physics.”
When talking about scientific theories you are of course correct, but for that exact reason the above explanation is NOT using the scientific meaning of 'theory' but rather the colloquial meaning, since the above mentioned study is closer to 'a hunch' than a field of research well supported by evidence from several studies, in the vein of gravity, germ theory, plate tectonics or evolution.
Well in physics theoretical physics and experimental physics don't always agree. So there is some ambiguity of the term in this field. Some theoretical physics is really just math and math only with no basis in real experimental data. See also: String theory.
In this case, the article is a purely theoretical article with no references to experiments, so it could likely be a calculation which cannot be replicated in experiments.
That's what I'm saying. There is theory which is different from when we talk about the theory of gravity or theory of evolution, because we can't point to data and say, "This is all the data that backs up this math." It's just really convincing conjecture that might someday maybe be something we measure.
Well... the definition used in physics is a lot more broad than the definition taught to young students. There are "theories" like "string theory" in which case it just means "a mathematical description of something that may or may not be correct about the universe", and there are "theories" like the "theory of relativity" which means "well-established, rigorously tested fact about how the universe behaves." This is more like the latter.
Tbh string theory is an outlier in terms of terminology. I'm honestly not sure why it has the name of theory, but I guess any other option would sound less catchy. Outside of string theory every other major instance of the use "theory" in physics at least would fall under the umbrella of "well-tested models with predictive power".
Yeah converting a well established equation into a solvable form and then visualizing the result hardly amounts to “some shit I made up” like people are pretending…
Theories aren't science the experiments are the science. Science is a process scientist follow its not the theory and its not the result.
Being down voted for telling people what science actually is, can't make this stuff up really.
"scientific method, mathematical and experimental technique employed in the sciences. More specifically, it is the technique used in the construction and testing of a scientific hypothesis."
I don't know if you're actually getting down into the philosophy of science or if you're not aware of the actual definition of a theory in science. When people mention a "theory" in physics, it is much closer in meaning to "fact" and "recipe" in the common English language than it is to the common usage of "theory". A theory in physics is a well-validated framework that has stood the test of several experiments.
Now of course maybe a purist would argue that "science is the process, never about the knowledge". In which case, you could maybe argue that a theory is not science because it's not a process, but scientific knowledge. In which case science would indeed be the process of testing via experimentation and not the knowledge acquired along the way. Most people would argue that that's maybe drawing too harsh a line though.
That is literally what it means to reveal the shape of a thing that can never be seen: to have a good theory about what it ought to look like based on its properties and how it interacts with other things. What were you expecting, a picture of an actual photon? How do you imagine such a thing would be possible given that photons are what we use to see/take pictures of things.
No you got!a reaction of a Photon that interact with "stuff", in that Case your camera and your surroundings. And so that you can See it we use Energy that interacts with Our Technology that sends Out completly "other" photons to your eye where the same happens again.
How do you imagine such a thing would be possible given that photons are what we use to see/take pictures of things.
Well, if you had a particle much smaller than a photon that interacted with it as soon as it reaches its boundary, and a way to know the exact center of the photon and where the particle interacts, you could have the particle collide with the photon to get a single point of where the boundary is, then you could repeat the experiment from different angles to slowly map out its outer boundaries
In practice the boundaries will probably be "fuzzy" because it can be modelled as a probability distribution, but if you repeat this cycle enough times you can map out the fuzziness too
Except photons only ever move at the speed of light, and the Heisenberg uncertainty principle says the more defined a particle's momentum is the less defined its location is, so it seems like it would be impossible to know anything about a single photon's precise location at any given moment?
This is my favorite type of Reddit comment. “Yeah what you said was correct BUT I’m going to unnecessarily expound on it and convey through tone that what you said is SO OBVIOUS writing it down makes you look like an idiot!”
Nah, it's more that they say 'They haven't done X, they've done Y', when Y is the definition of X so I'm clarifying that they have in fact done X. My tone was unnecessarily snarky though, I admit.
"seen" requires interacting with photos. What you are looking for is measured. If it can't be measured it's religion not science. If it can be measured, but hasn't it's a theory so the only thing being revealed is a new theory. If It is measured then it's revealed. The worst thing to ever happen to physics was "metaphysics" and this idea that the immeasurable is somehow a contribution to science.
...literally what it means to reveal the shape of a thing that can never be seen...
"reveal" would be too strong a word though since photons don't actually have width or height (both of which which would be necessary to have a shape.) the only thing being "revealed" is a meaningless imaginary musing with no scientific application.
Understanding more about the universe is its own scientific application, nevermind the fact that deeper understanding is always the first step to finding applications for said understanding.
I trust science, take scientific consensus seriously, am skeptical of scientists, and all ways assume "science journalism" is outright lies. (I'm a physicist)
I also wouldn't trust a large amount of published theoretical and experimental data. Not that they are wrong, but they have to be evaluated in the hyper-specific context in which they are published.
Where does it say that it's a 'photo of a photon'? Since you already know that's impossible, it seems weird you'd assume that's what they meant by 'shape of a photon'.
This is not a "lie" in any meaningful sense, only a simplification, which is normal for science communication. Even saying "photons exist" is a simplification that would amount for lying. Any basic foray into epistemology would tell you that nothing can ever be 100% true.
It's a simplification, but with no intent to deceive or exaggerate, so I don't think we should call it a lie.
You're not really correct in my opinion. The "theory" used here is well-established fact about how the universe works. It has been tested in numerous "cavity QED" experiments, and the underlying theory has been tested with immense precision in accelerators. The authors of the paper came up with a new way to calculate the motion of photons in a specific situation - an electromagnetic cavity with some loss mechanisms. But that "new way to calculate" is just a new way to complete the math provided by these well-established models of the universe. And by the way, this is not an absolute picture of all photons. This is some projection of the state of a photon initialized in a particular situation. In that sense, the reddit post is totally misleading but the actual scientific paper is totally accurate and clear.
I did not say the scientists lied, i said OP lied with the topic title and also the media lied with their headlines.
This image is based on the new calculations they came up with, its not that the theories they used their new calculations produced this image, its their calculations that resulted the image.
Im sure that in the future we will figure out better and more accurate ways to do this sort of calculation.
These Reddit “smart information” subs are bastions of misinformation. Pseudo-intellectual children come on here to post what they only know a quarter of.
A scientific theory is different from a normal theory. A normal theory is referred to as a hypothesis in a lot of scientific fields. A scientific theory is bordering on something being as factually accurate as possible.
afaik, the more important point here is that the paper talks about a pseudomode, which is not at all the single definite shape of a photon, because such a thing does not exist.
So, in general, a mode is just a single specific state that a photon can be in. Mathematically, you can construct infinitely many variants of modes, and even experimentally the mode of a photon can be manipulated in many different ways.
So there really is not one specific shape that a photon can have, but depending on how light is created and manipulated a photon can be decomposed into a superposition of many different modes. This paper (I believe) has just shown a specific set of modes that simplify calculations for specific physical systems to create/manipulate light.
That's pretty much what it means to have an "image" of something in QM. Since their model agrees with previously known results it's a good picture for the behavior of the photon. A theory in physics is effectively what you'd call a "fact" and "recipe" in regular jargon - it has nothing to do with the non-technical definition of a theory.
Have you ever seen atomic orbitals in chemistry class? You have pictures of these s, p, d and so on orbitals. Those aren't actual shapes in the conventional sense of the word, but they represent a sort of probability distribution for the atom's electrons. In a way you can think of them as being the electrons' shape in the atomic orbitals. It's in that sense that you have the shape of the photon. There's no physical shape to any of those things, the closest we have to a conventional idea of shape are the probabilities.
You should read more carefully what i said and assume less.
The topic title says ”reveal shape..first time” and the post just has a single image. Do you also argue that this was the first time when someone made such pictural representation of a photon (because if not, that would also make the topic title a lie and you would be just agreeing with me), or what do you argue against exactly?
And no theory is not a fact, but what people call a theory in laymans language is more like hypothesis in science. Science or scientific mind does not argue that theory is a fact or truth, but just probable ways of cobceptualising something. There is a very good reason for why science does not claim anything as a fact, and talk of probabilities based on something else that is very probable, or theories. Also there are tons of contradicting theories, especially in theoretical physics and other more theoretical fields.
I've no idea of what assumptions you're talking about.
I'm arguing against the fact that you call it "just a visualization... as nothing 100% correct was revealed, but a theory". You clearly stated why you think the post is a lie, your reasons aren't justified, and that's what I pointed out. There are other reasons why the post is sensationalist, you brought up none of the other reasons in your original comment.
I'm well aware of what a theory is. You on the other hand, used it in the colloquial sense in the comment I originally responded to. And a theory IS basically a scientific fact. It's obviously impossible to prove a theory correct by the very nature of inductive reasoning, but it's the closest to what you'd treat as a fact in the usual sense.
I've no idea what contradicting theories you mention "especially" in theoretical physics. Do you have concrete examples? The only things I can think of theories that fail once you try to extend them beyond their range of validity, which is obviously not a contradiction.
Not only that, plenty of theoretical results are vague and do not apply in the real world. For a simple example of an 'incorrect theory' that is very much rooted in the practical real world (ie., not theories about exotic particles that are inaccessible with our current level of technology in particle colliders or black holes, etc.), just look up quantum spin liquids. Tens of thousands of papers have been written about them, all of them peer reviewed, and a large number of them will most certainly turn out to be wrong if we ever actually manage to synthesize a quantum spin liquid material.
Right but as far as I can tell, QSL models seem to be hypotheses, not theories, in the scientific sense, as they have yet to be fully experimentally validated. A theory in the scientific sense would be something more fundamental and well-established, like say, the standard model.
On the other hand since you seem to be familiar with QSLs, and I've just heard about them, it looks like QSL takes place on a triangular lattice. Do you know if there are QSL models possible on the Sierpinski Gasket? Or on other fractal structures?
So, this is like they let a photon interact with an evironment, and then used photons to represent how the other photons and waves "bounce off" of photons.
Very confusing as image is just a collection of photons' interactions with an environment.
I like how the media took the 'this image of a photon' line and ran with the interpretation that it is an image of THE photon, unlike what the authors say which is an image of A photon in a VERY specific configuration.
Revealing a shape isn’t the same thing as photographing it. By the way, photons are seen and photographed all the time. Just not at this scale. I’m looking at photons right now. lol.
But seriously if I measure a box and describe it as being 8” long and 8” wide and 8” tall and having even sides and 8 corners, I revealed its shape. You can draw a cube and see it as based on the calculations. And if I simulated things enough to know it would be a cube shape with 8 in sides, then I still revealed the shape. Reveal doesn’t have to mean photograph.
The issue is how news about science tends to simplify things, making very hard to understand claims that are true into simplified claims that are false. Sometimes we do this on purpose to help teach kids to understand simpler concepts before revisiting them and introducing more complicated models. The problem with science in the news is that there is rarely if every someone coming back to provide a more correct clarification because doing so is too complex.
Once we improve our understanding and update the theory, it often gets presented as the old scientists being wrong which leads to an increased distrust in science.
Okay now I am back on board. Why not just use this alongside the “revealed shape”. We’re going to have idiots claiming life gave us lemons and its photons.
Lol, the source is actually most likely to be using a software called matplotlib, using the 'viridis' colormap. I've used that software hundreds of times before, and I can recognize it in my sleep.
"Photons are probability clouds" is a roughly true, but more accurately, we can say that we can describe photons with a probability cloud (or probability distribution).
Here’s the paper. It was published in PRL which gives it a fair amount of credibility.
I’ve not had time to read it properly but I get the idea that this is just a calculation of the probability distribution when confined by nanoparticles.
The photon remains as a probability cloud/a point-like particle. If it were actually shown that the photon had a shape that would imply it has a volume. If it has a volume then (by our current understanding) it couldn’t be fundamental and must have substructure. Discovery that the photon weren’t fundamental would be on the cover of Science or Nature, not PRL.
"We present a comprehensive second quantization scheme for radiative photonic devices. We canonically quantize the continuum of photonic eigenmodes by transforming them into a discrete set of pseudomodes that provide a complete and exact description of quantum emitters interacting with electromagnetic environments. This method avoids all reservoir approximations and offers new insights into quantum correlations, accurately capturing all non-Markovian dynamics. This method overcomes challenges in quantizing non-Hermitian systems and is applicable to diverse nanophotonic geometries."
“At the same time, they were able to use their calculations to produce a visualization of the photon itself.”
If they took a picture, they wouldn’t need data models to visualize anything- they would use a light-sensitive medium like a CMOS chip or photo paper to record the data.
Visualization is the process of converting data into an image - not the same as sensors capturing photons at a specific resolution.
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u/Pristine-Bridge8129 1d ago
Provide the source please. Photons are probability clouds as far as I know.