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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 go
by namanyayg 11mo ago
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
- thaumasiotes 11mo ago> But actually everything is merely waves and fields. The two-slit experiment says otherwise.
- FloorEgg 11mo agoThe 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.
- gucci-on-fleek 11mo agoHmm? The double slit experiment definitely shows that particles are waves—weird quantum waves, but still waves.
- fragmede 11mo agowhat happens when you only send a single photon down the line though?
- mpyne 11mo agoIt's worth reading about, but it's kind of wave-like even then: https://en.wikipedia.org/wiki/Double-slit_experiment#Interference_from_individual_particles 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.
- binary132 11mo agoThe way I read GGP was as contradicting the assertion that everything is just waves and not at all particles.
- rolph 11mo agodo it once, it looks like one particle. repeat the single photon launch many times, and you see a wavelike distribution of photon strikes
- bobbylarrybobby 11mo agoIt 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.
- ggm 11mo agoI'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.
- uberduper 11mo agoDouble 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.
- ggm 11mo agoNot a physicist, just here to observe single photons weren't reliably emitted until the modern era. like the 1970s. The double slit experiment pre-dates this. it's from 1801. The one which confirms "self interaction" was 1974. I was in high school 1973-78 so the stuff we did, was comparatively "new" physics in that sense. Not a message I remember receiving at the time. From the pop-sci history reading I do, "detecting" reliable generation of single photon STREAMS in the early days depended on using mechanisms which inherently would release a sequence of photons on a time base, over time, and then gating the time sufficiently accurately to have high confidence you know the time base, and can discriminate an "individual" from the herd. I don't doubt quantum theory. I only observe it's mostly for young students (like almost all received wisdom) grounded in experiments which don't actually do what people think they do. The ones you run in the school lab are illustrative not probative. What people do in places like the BIPM in Paris, or CERN, isn't the same as that experiment you did with a ticker-tape and a weighted trolleycar down a ramp. "it's been confirmed" is the unfortunate reality of received wisdom, and inherently depends on trust in science. I do trust science. Now we have quantum dots, and processes which will depend on reliably emitting single photons and single electrons, the trust has moved beyond "because they did it in CERN" into "because it's implemented in the chipset attached to the system I am using" -QC will need massive amounts of reliably generated single instance signals.
- danparsonson 11mo agoIt'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 :-)
- gucci-on-fleek 11mo agoAs 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 https://www.feynmanlectures.caltech.edu/III_01.html#Ch1-S5 [1]: https://en.wikipedia.org/wiki/Wave%E2%80%93particle_duality#Electrons_behaving_as_waves_and_particles https://en.wikipedia.org/wiki/Wave%E2%80%93particle_duality#...
- prmph 11mo ago> 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.
- WJW 11mo agoDepends 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.
- thaumasiotes 11mo agoThe 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.
- deleted 11mo ago[deleted]
- layer8 11mo agoEverett reconciled that. They only appear to fail to behave like waves because the observer is waves as well.
- jasonwatkinspdx 11mo agoIt does not. It shows that individual photons self interfere, so they cannot be idealized particles.
- dcl 11mo agoAre you getting confused with the photoelectric effect experiment?
- farrelle25 11mo agoAnother 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 https://arxiv.org/abs/quant-ph/9502017
- mock-possum 11mo agoPilot wave is still my favorite - I don’t really believe it, but I like the image
- deleted 11mo ago[deleted]
- naasking 11mo agoIt is indeed a great way to translate classical intuitions to the quantum domain.
- rhdunn 11mo agoVeritasium 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 https://www.youtube.com/watch?v=WIyTZDHuarQ
- jagged-chisel 11mo agoThat we're just collections of wave interference is wild.
- isolli 11mo agoWe're built on so many layers of emergence, it's wild! quantum particles => atoms => chemistry => biochemistry => cellular life => multi-cellular life => intelligence
- piva00 11mo agoIt 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.
- jacquesm 11mo agoI like your progression. It makes me wonder if intelligence could lead to technology absent societies.
- boyanlevchev 11mo agoIf 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.
- vixen99 11mo agoAfter a brilliant start (atoms etc.,) it starts to be problematic once one hits societies. After all, the earlier progressions are undeniably astounding stable successes in their various incarnations. A pessimist might say 'Stable' societies so far have tended eventually towards being self-destructive tyrannies.
- canjobear 11mo agoThere'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.
- sosodev 11mo agoBut there’s no quantum explanation of gravity, right?
- arthurcolle 11mo agoClassified
- lmpdev 11mo agoAt this point we have several They’re all largely untestable though String theory, LQG, half a dozen others
- fnordpiglet 11mo agoThere’s no explanation of gravity, quantum or no. There are merely descriptions.
- isolli 11mo agoIsn't everything descriptions, in the end, aka models? Turtles all the way down...
- B1FF_PSUVM 11mo ago"Two masses attract each other with a force F = m1 m2 G/r^2" "OK, but why don't they repel each other?" "That would make life really hard, and we wouldn't be here discussing it ..."
- tsimionescu 11mo agoActually, 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.
- hliyan 11mo agoI 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.
- setopt 11mo agoI 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.
- IAmBroom 11mo agoThank 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.
- chadcmulligan 11mo agoI don't have the math, but doesn't quantum field theory say this?
- gethly 11mo agoMaybe think of it as binary(particles) vs analog(waves).
- baq 11mo agoJust 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 https://www.youtube.com/watch?v=MO0r930Sn_8)
- zyxzevn 11mo ago3Blue1Brown 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 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 https://progress-in-physics.com/2014/PP-37-06.PDF And here is his book. https://drive.google.com/file/d/1BlY5IeTNdu1X6pRA5dnJvRq3ip6cRKTg/view https://drive.google.com/file/d/1BlY5IeTNdu1X6pRA5dnJvRq3ip6...
- ta988 11mo agoThere are so many artifacts that could cause those observations that I emit serious doubts that's what is happening in those experiments.
- uberduper 11mo agoWhat 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?
- moi2388 11mo agoBecause quantum mechanics describes the universe with a wave function, which evolves according to the schroedinger equation. In it, there is no notion of collapse. The only thing that makes sense is saying the observer becomes entangled with the measurement. So if you only look at the Schrödinger equation, this is the only conclusion. Wave function collapse is something which is simply added ad-hoc to describe our observation, not something which is actually defined in QM
- uberduper 11mo agoThat's an unsatisfying answer. I have some work to do if I want to understand it.
- sevensor 11mo agoI disagree. Our notion of waves is no less an analogy to macroscopic phenomena than billiard balls. There’s no avoiding the dual nature, and there’s no problem with saying that the wave analogy works in some places, but the particle analogy works in others. The only real truth here is “neither.” A photon is a photon, and there is no macroscopic analogy it reduces to perfectly.
- szundi 11mo ago[dead]
- user3939382 11mo agoSoon!