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Quantum Physics Just Got Less Complicated
wabrandsma sends this news from Phys.org:
Here's a nice surprise: quantum physics is less complicated than we thought. An international team of researchers has proved that two peculiar features of the quantum world previously considered distinct are different manifestations of the same thing. The result is published 19 December in Nature Communications. Patrick Coles, Jedrzej Kaniewski, and Stephanie Wehner made the breakthrough while at the Center for Quantum Technologies at the National University of Singapore. They found that wave-particle duality is simply the quantum uncertainty principle in disguise, reducing two mysteries to one.
"wave-particle duality is simply the quantum uncertainty principle" gets a "no shit" straight away from me, though I guess a rigorous proof of it is kind of news.
I'm sure cosmonauts Dorothy, Blanch, Sophia, and Rose would have no troubles with Quantum Physics.
It sounds like they are now only few steps away from discovering the Schrödinger equation.
...to not be two distinct phenomena.
Word substitution: The easiest way to make new scientific discoveries.
TFS is so stupid there's no way I'm going to RTFA.
Comments like this are like urine stains on the wall next to public urinals. They appear so often and so consistently you'd think there was a contest, where the first one to miss, wins.
<blink>down the rabbit hole</blink>
Seriously guys, we need to drop the copenhagen interpretation already. Pilot-wave theory eliminates the need for quantum mysticism.
"Violence is not the answer. Violence is the question. The answer is yes."
Of course! This clears up everything! Now I understand quantum physics completely!
When someone says, "Any fool can see
I thought that Pilot Wave Theory answered this "uncertainty"?
Wow, loving all the ACs calling this obvious, who clearly didn't even make it to the abstract! "Such wave-particle duality relations (WPDRs) are often thought to be conceptually inequivalent to Heisenberg's uncertainty principle, although this has been debated."
Clearly, all you armchair physicists need to set those ivory-tower morons straight!
Can we say that this new discovery is a Quantum Leap? What do you think, Al?
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I only have one quantum mechanics course under my belt, but this was already my intuition. The wave equation describes the uncertainty in the particle's position, but the particle is not actually a point-like mass but a sort-of localized fluctuation or perturbation in ... something. I imagine a particle as a non-Newtonian fluid that hardens (collapses the wave function) whenever a force (observation/measurement/external interaction) is applied. In any case, very cool that somebody has "proved" this to be the case (no, I did not RTFA).
Heisenberg was walking in a field on a chilly night, looking at the stars, when it came to him.
Really.
Here we show that [wave-particle duality relations] correspond precisely to a modern formulation of the uncertainty principle in terms of entropies, namely the min- and max-entropies. This observation unifies two fundamental concepts in quantum mechanics. Furthermore, it leads to a robust framework for deriving novel WPDRs by applying entropic uncertainty relations to interferometric models.
So they're looking at it in terms of entropies, and when they do, it resolves a debate about whether WPDRs are equivalent to the Uncertainty Principle AND generates new WPDRs.
There is a wide gulf between suspecting two phenomena are related, and having discovered the rigorous mathematical framework that lets you translate discoveries from one theoretical framework to the other without losing information.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
I'd love to read a real comment (yeah, I know, it's almost like I'm new here) from someone who is actually capable of understanding the math here. It would be great to see a reasonable discussion on the actual implications here.
As to people saying "that's obvious" -- what you can intuit and what you can prove are not the same thing. The only thing prove by a "that's obvious" comment is that the person posting it doesn't have a clue.
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
44 years late to the party. I've got a 1970 high school physics textbook that says that, and goes on to demonstrate this with math accessible to high-school physics students.
If you put water in a cup, it magically forms the shape of the cup.
This is one of several recent articles that seems to be tying everything to Entropy. There have also been recent theoretical pushes towards defining the flow of time in entropic terms, gravity in entropic terms, superconductor behavior in terms of entropy, etc. This is in fact the second recently article trying to tie quantum mechanics to entropy in different ways. It seems, from an outside pov, like the physics world is starting to converge on entropy as the underlying, unifying thing. One the one hand that all sounds really positive: real progress on unification! On the other hand, defining everything terms of information/entropy sort of seems to sidestep all the really hard questions. It leaves us with a universe that isn't necessarily, fundamentally understood to any greater depth than it was decades before. It just means we probably can't tell if we're in a simulation because we're defining reality as simulate-able.
If something gets simpler, the entropy of the universe decreases. It can't happen. It is the law, everything should get more and more complicated as time goes by. Why, the next generation will have easier time to pass Quantum Mechanics I PH304 MWF 10:00-11:30 than I did? Would not stand for it.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
"wave-particle duality is simply the quantum uncertainty principle" gets a "no shit" straight away from me, though I guess a rigorous proof of it is kind of news.
That's how science work. You don't base your decision on the mere principle that it more or less looks kind of logical.
(After all, it only looks "kind of logical" to your *brain*, which has spent the last few million years being optimized to help bipedal monkey survive together in the savanah. Actual science can some time feel "weird" and defy logic, because it defies the monkey-brain logic. - e.g.: the sum of all positive integer is a negative fraction)
You do thoroughly prove that by the numbers.
Yes, the double-slit experiment (where single particle behave like waves) strongly suggest that the uncertainty principle is at work (there's not *a signle photon* going through the slits, it's instead a function showing the distribution of the probabilities to pick it up at a certain place).
Now, we have mathematical proof that's indeed the case.
Science: the only place where it's actually correct to spend the time and mental ressource to formally prove that water *is* wet, and fire *does* burn. Because, along the way, you develop mathematical tools which come handy to do more advanced science.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
from slashdotters who all want each other to think they know what the fuck they're talking about.
You are clearly wrong. The Cat is neither alive nor dead, and heralds the birth of the zombie apocalypse. Run while you still can!
The public urinal in this case being public physics journals!
It's an interesting revelation but still only serves to highlight our ignorance. It's still wrong. Light is not something I would even define in terms of a particle or a wave. It's a manifestation of pure space with a collapsed time function. Light is a wave. It manifests as a particle only because it momentarily ceases to be light - converting into an excited state of an electron as it passes through matter.
Someone needs to invent a urinal aiming sticker for /. comments.
I'm not a physicist - and I worked most of this out myself years ago - cf. http://slashdot.org/journal/35...
This comment was written with the intention to opt out of advertising.
Ok, let me give this a crack.
You build a box. That box contains a Geiger counter, which clicks if it detects the decay of a particle. Because you're a sick, sadistic fuck, you hook up that Geiger counter to a hammer such that if the Geiger counter detects the decay, it engages the hammer to smash a vial of poison, thus releasing it into the box. You then--because, as I said, have issues with sociopathy--put a cat in the box and close the lid. The box is very thick, completely opaque and completely soundproof. You have no way of knowing what's going on inside the box.
You wait an hour. In that hour, you do some maths that shows that there was a 50% chance that the particle decayed, triggering the Geiger counter, which triggered the hammer to break the vial of poison, releasing the gas and killing the cat.
The question becomes: before you open the box, is the cat alive or dead? Or is it somehow...both?
Your gut instinct is to say, "That's stupid. Of course it's either alive or dead. How the fuck could it be both?"
But the thing is, there are certain, non-cat-related experiments that we've done that REQUIRE the answer to be BOTH. Perhaps the simplest (and certainly the one we physicists learn about first) is the double-slit experiment. The basic idea is, you shoot a beam of something (light, gold atoms, DNA, doesn't really matter) at a slit, and it forms a pattern on a wall. It'll form this pattern even if you shoot your particles one at a time. Then, you close that slit and open another one, and fire your beam again. It forms a different pattern.
Now you open BOTH slits and fire your beam. What happens? Well, what you'd expect is to get a pattern that's the SUM of the pattern you get through each slit. That corresponds to the idea that the particles each go through either Slit 1 or Slit 2. But instead what you get is an INTERFERENCE pattern, which can ONLY happen if the particles are going through BOTH HOLES. And recall I said earlier--you get the same pattern even if you shoot your particles one at a time, which means THE PARTICLE MUST BE INTERFERING WITH ITSELF.
So back to the cat: is it alive or dead, or is it alive AND dead? According to the Copenhagen Interpretation, it's both. But that's why the cat thought experiment was devised in the first place: to highlight how RIDICULOUS that was. The crazy thing is that, seventy years later, we don't really have a better interpretation (at least not one that's widely accepted). So until someone builds this possibly-cat-killing box, we won't really know if the Copenhagen Interpretation is right, or whether something even stranger goes on when quantum events get amplified to the macro level.
One final note: practically speaking, there's no way to build this experiment, because of the whole "you have no way of knowing if the cat is alive or dead without opening the box" part. Isolating a system as big as a cat-box from the rest of the universe is not really feasible. You would also have to construct a particle decay detector that did not, itself, "collapse" the waveform of the decaying particle (otherwise the paradox is resolved before you ever make it to the cat).
Hope that was helpful!
But surprised they don't use the correct word: (a)ether.
I come here for the love
Exactly. You don't even need to look at math to understand this.
Thanks for taking the time to type that out. It gave me a starting point to learn more, and I learned that if you release particles one a time, each particle makes one mark, one dot. One particle doesn't interfere with itself, and can't because the interference pattern is seen in the density of collisions over an area.
As many of these single dots build up, they tend to cluster around an interference pattern - as if some particles went through one slit, and some particles went through the other slit. Well yeah, if I turn on the light in my living room, some photons go out through one window, some photons go through the other. Each goes through one or the other.
So I do very much appreciate it, yet I'm as yet unsure where to go to "get it", to have the ahah moment of "this is what it's all about!"
> you'd expect is to get a pattern that's the SUM of the pattern you get through each slit. ... But instead what you get is an INTERFERENCE pattern
I thought the definition of the word "interference pattern" is "the SUM of two waves". So you'd expect a sum, and you get a sum, which is called an interference pattern.
Again, thanks.
ISBN?
One particle doesn't interfere with itself, and can't because the interference pattern is seen in the density of collisions over an area.
As many of these single dots build up, they tend to cluster around an interference pattern - as if some particles went through one slit, and some particles went through the other slit.
Not quite--and that's really the key element of this whole thing: the particle somehow DOES interfere with itself, because the interference pattern that builds up, just one particle / one dot at a time is DIFFERENT than what you'd get if each particle only went through one hole. Imagine you're up on a ladder, dropping beanbags through a plank with two slits in it (you can cover those slits if you want), and they form a pile on the ground below. If the beanbags can only go through one slit, the pile you get on the ground is a nice mound. If you open up BOTH slits, then what you expect is TWO mounds. If the slits are close enough together, you expect those mounds to overlap, with the height at each spot being AT LEAST AS HIGH as the height you'd see dropping the beanbags through just one hole.
But instead, what you see in the double-slit experiment is that, in between the two mounts, you get spots where there are FEWER beanbags than you'd get dropping them through just one hole. Somehow, instead of getting that 1+1=2, you're finding that 1+1=0. The beanbags are all still there--it's not like they're cancelling each other out.. they're just not all where you'd expect them.
The ONLY WAY to explain this (that we've found so far) is if each beanbag, which, again, you're dropping one at a time, somehow goes through BOTH slits and INTERFERES WITH ITSELF. This is where the idea of wave-particle duality comes in, because the patterns that you see (with valleys where there should be ridges) are similar to what you'd see with water waves or sound waves (sound waves can cancel each other out--that's the whole premise behind noise-cancelling headphones).
So then why don't we just say that photons (and beanbags) are waves and not particles at all? Well, because classical waves aren't "quantal," meaning you can't divide sound waves into discrete, indivisible components. You can have one "particle" of light (a photon). There's no corresponding discrete element of sound. So we say that they're particles after all, and simply adjust our thinking regarding just what a particle is and how one behaves.
Good redux.
But I still can't help but feel that the whole common understanding (or lack thereof as it seems to be) is based on something broken.
Then I discovered Pilot Wave Theory, which suggested to me that a particle by its nature may be surrounded by a wave.
That is, it truly IS both at the same time; not particle and wave, but particle WITH a wave. -So that it carries both properties, but not in the magical-thinking "wooo" way. It's a particle which creates ripples as it moves and those ripples affect how it interacts with and bounces off things.
This would make it *not* magic. Not spooky. -Hard to calculate, sure, but it just means our math to this point has been trying to describe something we were visualizing incorrectly and making poor assumptions about. (And writing altogether too much bad sci-fi around.)
In other words.., according to the pilot wave theory, Schroedinger's cat really is dead OR alive. You still need probability maths to make educated guesses as to which it is, but it's no longer prudent (or excusable) to think that it is actually both at the same time until some egocentric scientist looks in the box. (As if the cat's opinion doesn't matter).
So... Did that just kill all the science fairies?
Newtonian physics looks kind of logical. It's completely wrong, but plenty of decisions are based on it. Despite that we know is wrong
It's not *completely* wrong.
In fact back then when it was discovered, it was experimentally proven to work within the parameters which were tested.
The reason it was used then and is still used now is that within this range of parameters, it still works. For everyday use, what newtonian predicts is within what is observed. That's a precise enough model.
What happened is that scientists started to consider much more extreme paramters range (higher energy, faster speed). At that point, newtonian physics breaks down. Does it mean that all the past results were wrong ? No it simply means that it's a model which is only works within a certain range of parameter (it's good for everyday use - you car) if you need to consider parameters outside this range (space ships, planets) you need a better model (general relativity, etc.)
Note:
- with Newtonian physics we speak about a physicis model. About a model that's used to approximate real-world events. This kind of things only get experimental proof (prediction fits the measured data or not). And will eventually get superseded by a better model which works better including for some corner cases or at higher range, smaller scales, etc. (String theory and such were born as a tentative at a better model than the dichotomy between relativity and quantum mechanics).
- with TFA: it's a bout a *mathematical proof* that 2 different models are really actually the same stuff just expressed in different ways. Take one model, tweak the equations, and you should obtain the other model. It doesn't speak about the quality of the models themselves, just the mathematical links between them. ...but usually, when you have a newer model, that is better experimentally, you usually also need to find a mathematical "link" between the two, an explanation why the old model used to work and only got contradicted in your experiment.
(I fact, the quantum mechanics model has its limitation - what you call "wrong" and what I call "use it only within the range of value where it works the best.
QM works best at predict very small scale phenomena (particles, waves, etc.). QM completely sucks at being useful for anything at the other end of the scale: QM is a piece of shit for astronomy. And vice versa: relativity is good when you consider stars, useless when you consider particles. 2 models, each best at a different scale. And strings being a possible future model that could simultaneously work at both scales.).
e.g.: take the relativity equations, and use them to compute the motion of your car - the level of energy and speed are so small, that all the "weird parts" of relativity can be approximated and rounded to 0, what remains ends up looking exactly like newtonian physics. Newtonions physicics are the same, simply with the relativity parts neglected, because they don't play any significant role at that scale.
Science constantly bases decisions on kinda logical principles until those principles are proven to be wrong.
Newtonian physics looks "kind of logic" because it's a model designed and tested and proven to predict a range of events (reasonable speed, low energy, human-size scale instead of particles, etc.) which happens to match what our monkey-brain have evolved to cope with.
(our ancestrors never had to think about nuclear bombs, supernovae, tunnel effect in electronics, etc.)
That's also why it got discovered first (we didn't first invent relativistic physics and the newtonian as handy simplified formula for some type of problems), because that's what was easiest for our monkey-brain to think about.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
So I haven't read too much into pilot wave theory, but it's a hidden variable theory, and according to Bell's Theorem, you can have hidden variables, you can have "locality" (meaning no action at a distance), but you can't have both. And most physicists would MUCH RATHER have locality than hidden variables.
Well, the truth is we have the non-locality anyway. Whatever happens which reduces the measurement to a definite result is non-local. And - ofcourse - there has to be something like this. Stil, I am not too convinced by the pilot wave theory, but it is at least an attempt to deal with the inherent problems of QM by trying to create a proper physical theory, not by philosophical bullshit.
Ah, but that's where it gets interesting. Interference pattern is sum of _waves_. But you're shooting _particles_. Where'd waves come from? Are the particles acting like waves? Is there anything else that seems like it could act like waves? Don't see anything... guess it must be the particles. But why are particles acting like waves?
The single slit "pattern" is pretty simple: lots of hits near the center, decreasing smoothly as you get away from the center. Not a complex pattern, and not one where adding a copy that's offset a bit would be expected to make a huge difference - two maximums instead of one, with a bit of a decrease between them, and larger decreases as you move outward. But what is actually seen is much more complex, and appears to require the summing of either more than two simple patterns (in which case, why are you getting more than two simple patterns from two slits) or two not-so-simple patterns (in which case, why are you getting not-so-simple patterns now when you got simple patterns with one slit).
(Posting anon to avoid canceling moderation)
If you put some steel across a span with lots of triangle shapes to it, intuitively you may look at it and say "should hold". I'd probably walk across it willingly. I would not, however, want to count on driving trucks over it regularly without someone with engineering training and rigor applying math and proven science to the problem first.
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
the rigorous mathematical framework
Like the one shown in Volume 3, Section 2-2 of the Feynman Lectures of Physics, published 1964?
Now this property of waves, that the length of the wave train times the uncertainty of the wave number associated with it is at least 2, is a property that is known to everyone who studies them. It has nothing to do with quantum mechanics. It is simply that if we have a finite train, we cannot count the waves in it very precisely.
.: Semper Absurda
Maybe you're thinking of The Feynman Lectures (which is college-level)? In Volume 3, Section 2-2 of his lectures, Feynman shows the deep relationship between the uncertainty principle and wave-particle duality. Feynman sez:
Now this property of waves, that the length of the wave train times the uncertainty of the wave number associated with it is at least 2, is a property that is known to everyone who studies them.
.: Semper Absurda
Aha. That is interesting. A set of particles that move/act like a wave is one thing, but in this case one slit doesn't look like one wave, but two slits looks like two waves. Interesting.
I think people are moving away from the Copenhagen interpretation to other interpretations such as consistent histories, decoherence, and many worlds. Bohmian interpretation is another option, but I find it inelegant and it doesn't hold too much sway.
Personally, I feel that consistent histories* is the best. In this interpretation, the cat is simply dead or alive. We don't know which until we check, but the cat's state didn't change when we opened the box. Note that whatever is enforcing consistency does not obey causality---the laws of quantum mechanics are essentially symmetric in time (more accurately CPT). In some sense, the future is "prewritten" though we have no way to measure it, and the current state of the universe is required to be consistent with the future state. So if the cat is dead in the future where the box is opened, it's already dead with the box closed.
I prefer the "block universe" depiction of the universe as a stationary 4D object, since it seems to be easiest to reconcile with relativity. Relativity of simultaneity makes no sense if the future isn't already written. We call this 4D universe object a history, and all the events in the history have to be consistent with laws of physics. It makes no difference if you think of the past causing the future or the future causing the past: they are just there and neither is created from the other. In the many worlds interpretation, every possible (e.g. consistent) history exists, but I think one is sufficient.
*I might be mistaken on what consistent histories is. My description is my personal interpretation, which might coincide with the definition of consistent histories.
Could the single particle be interacting with with particles sent through in the past or future? Could the wave function describe the ensemble, since it is the ensemble that forms an interference pattern, not the first particle?
No idea why you were modded down for this. The damage has been repaired, good sir. Please return to your Bennett Haselton related downmodding...
On the other hand, New Scientist reported on a new approach with leaky (non-infinite) multiverse that can explain away both of these uncertainties. It's at least an interesting read.
Ghost universes kill Schrödinger's quantum cat
To quote:
"THE wave function has collapsed – permanently. A new approach to quantum mechanics eliminates some of its most famous oddities, including the concept of quantum objects being both a wave and a particle, and existing in multiple states at once."
Probably not, that sounds like a qualitative observation. How exactly would you use that to translate an arbitrary new discovery about the properties of particle/wave duality into an equally rigorous description of uncertainty properties?
--- Most topics have many sides worth arguing, allow me to take one opposite you.
It is an 'Urban Legend' that any THINKER ever considered the Earth to be flat. The First Humans to look at to see and contemplate what the horizon implied realised that the Earth was CURVED. Looking at the soon and moon was a BIT of a clue as well. Modern sheeple, in their UNIVERSAL schooling (and the people behind universal schooling were about societal control, NOT education), are told all kinds of lies in all kinds of lessons.
Also, the cretin who does not understand the mathematical concept of first, second, etc., approximations is a classic example of a Beta puked out from one of these non-education machines- idiots who THINK themselves smart. I recall, at a much BETTER school, being blown away when we got to the topic of relativity, and were given the relationship between the Newtonian approximation, and the more accurate physical model that emerged with relativity. It was such a neat merging of concepts in scientific models and mathematical theory. Common core maths teaching will ensure as few as possible future students will glory in such comprehension.
Isaac Asimov a 'great scientific mind'? Hahahahahahahahahahaha! But he DID have an inquiring mind and a respect of knowledge, and at least attempted to guide his readers in a good direction. But as a 'thinker'- well he was a great example of a person working VERY hard to make the best of very little- and that I admire.
The basic idea is, you shoot a beam of something (light, gold atoms, DNA, doesn't really matter) at a slit ...
I see what you did there.
When did it become the "quantum" uncertainty principle? I'm sure Heisenberg was not happy when we switched to the truncated "uncertainty principle," and even further to simply "uncertainty." But who's the asshole that added a superfluous and nearly meaningless word to an old concept? WHO REBOOTED? AND WHY?
The Admin and the Engineer
The quote I used comes at the conclusion of a mathematical demonstration - here's the link. I've now had the time to read the new paper (TFA), and they actually credit Feynman right at the start for having the general insight. Feynman's discussion is for a single uncertainty relation (position and momentum for a "particle" composed of a finite wave train), while TFA is broadly general and cached in terms of the modern entropy-based approached to uncertainty. So I think you're right, in that Feynman's treatment can't really be called a "framework" - it only deals with a single problem.
Really the only problem here is gross overstatement in TFS...but what else is new.
.: Semper Absurda
which is what the summary could have said
Stephanie Wehne
Stephanie Wehner is a physicist and computer scientist at QuTech, Delft University of Technology ... She studied at the University of Amsterdam and obtained her Ph.D. at CWI, before moving to Caltech as a postdoctoral researcher ... From 2014, she is an associate professor at QuTech, Delft University of Technology. Together with Jonathan Oppenheim she discovered that the amount of non-locality in quantum mechanics is limited by the uncertainty principle. She is also known for introducing the noisy-storage model in quantum cryptography. Before academia Wehner was involved in computer security, for example kernel rootkits, and for a while worked as a professional hacker.
To put it simply, the double-slit experiment is absolute proof that photons are waves -- you can't get an interference pattern from particles. Conversely, the photoelectric effect is absolute proof that photons are particles -- waves don't quantize.
I think it does exist. It's the word "beta".
But instead what you get is an INTERFERENCE pattern, which can ONLY happen if the particles are going through BOTH HOLES.
To me, this is one of the most famous physics experiments of all time... but I have never been able to find out how far apart those holes are and at what distance the holes are apart that the single photon stops traveling through both.
It seems to me if the slits (holes?) have to be closer than the uncertainty of the position of the photon then we are dealing with something other than what we call "physical reality". Call it a sort of building block for "physical reality".
Hm?
"Someone needs to talk to the tree of liberty about its ghoulish drinking problem." by ohnocitizen
I'm so happy about this news, I'm gonna shove a cat through 2 slits to see what happens.
Table-ized A.I.
Give the man an A for effort!
Slashdot mods, why don't you remove this shit??? I don't want to have to change my filter settings. This is your last warning: Remove this and things like it or I (who am very connected to science, tech, and academia) will make sure you lose so many members your member base will look like a random handful of reddit users.
And, if you think this is about censorship, you are incorrect. Some people have mental disorders that cause compulsive pointless posting. We need to distinguish between real posts, and posts made by mentally disturbed people who don't realize what they are doing, or why they are doing it.
The question becomes: before you open the box, is the cat alive or dead? Or is it somehow...both?
Your gut instinct is to say, "That's stupid. Of course it's either alive or dead. How the fuck could it be both?"
But the thing is, there are certain, non-cat-related experiments that we've done that REQUIRE the answer to be BOTH. Perhaps the simplest (and certainly the one we physicists learn about first) is the double-slit experiment. The basic idea is, you shoot a beam of something (light, gold atoms, DNA, doesn't really matter) at a slit, and it forms a pattern on a wall. It'll form this pattern even if you shoot your particles one at a time. Then, you close that slit and open another one, and fire your beam again. It forms a different pattern.
The problem is, the double-slit experiment doesn't tell you a thing about the cat.
Any single run of the cat experiment will have the cat either alive, or dead, before you open the box. 50% will be one, and 50% will be another.
Firing electrons at slits -- 1 or 2 -- does not change the fact that the electrons do have a location. We may not be able to measure it -- measuring requires an interaction, and the interaction will change what happens. There's a number that represents that ultimate limit -- plank's constant.
Toss electrons, one at a time, through a slit, see one pattern. Fine.
Toss electrons, one at a time, through another slit, see a different pattern. Fine.
In each case, you have electrons with a location. Different electrons have different locations. You don't get spots, you get slits. But slits made of one spot, then another spot, then another spot, etc. Each electron hits the screen at one point. Each electron has one location. Each cat is either alive or dead.
Toss electrons through a pair of slits, with detectors measuring the electrons: See a pair of slits (no interference) on the screen.
Remove the detectors: see the interference.
But in each case, you see spot, spot, spot. The final outcome location is different. The electron's path may not be linear, it may be doing quantum tunneling from point A to B as it "moves". In the process, it may move near the second slit, before coming back. Hence, the ability to "Detect the non local slit" and change the path.
But it has a single spot when you measure it.
The cat has a single state.
We may have no tools to describe it other than "We don't know, but a 40% chance of here, a 10% chance of here, a 10% chance of there, etc.". We may have no tools to describe it other than "We don't know, but a 50% chance of being alive".
It is not both.
It is "we don't know".
It is "we can not possibly know -- the universe does not let us know without changing the outcome".
But "Cannot know" is not the same as "Does not exist".
====
What is the "width" of an electron?
Since the location of an electron has uncertainty, there is a concept of "width" -- the area in which an electron might be found if you measured it.
If you have a single slit, then you are filtering out the "wide" electrons, that are too far off.
If you have a double slit?
If the two slits are close enough, that the "width" of the electrons includes both slits, what does the result look like? If the slits are far enough apart, that the width does not include both, what does the result look like?
My understanding is that if the two slits are far enough apart, you do NOT get any interference patterns.
The basic idea is, you shoot a beam of something (light, gold atoms, DNA, doesn't really matter) at a slit, and it forms a pattern on a wall.
But tossing bigger things at the slits means that the slits have to be closer to see the interference, and the slits have to be bigger to let the things through. Eventually, the "closeness" of the slits and the "wideness" of the slits means that you have one slit, not t
Why!
nassim haramein must be rolling over in his van.