A single neutron moves along two paths simultaneously, in clearly quantifiable proportions:
The double-slit experiment is the most famous and probably the most important experiment in quantum physics: individual particles are shot at a wall with two openings, behind which a detector measures where the particles arrive. [...]
"In the classical double-slit experiment, an interference pattern is created behind the double slit," explains Stephan Sponar from the Atomic Institute at TU Wien. "The particles move as a wave through both openings at the same time, and the two partial waves then interfere with each other. In some places they reinforce each other, in other places they cancel each other out."
[...] Of course, this wave distribution cannot be seen by looking at a single particle. Only when the experiment is repeated many times does the wave pattern become increasingly recognisable point by point and particle by particle.
They set up a double-slit experiment using neutrons as a source, but they also manipulated the spin of the neutron. If you flip the spin on only one of the two paths, you can tell which path the neutron took; however, when you do this, the double-slit interference pattern disappears due to quantum complementarity. Instead of flipping the neutron spin, they only change the spin a little bit, which preserves the interference pattern, but they only gain a little bit of information about which path the neutron took, so they still have to use many neutrons to build up the interference pattern.
They were able to show that if you reverse the applied rotation to the beam after it had recombined, you can determine through which path the neutron went for each individual neutron. If it had taken only the path on which the spin has been rotated, the full angle of rotation would be necessary to rotate it back. If it had taken only the other path, no reverse rotation would be necessary at all.
Through detailed calculations, the team was able to show: Here, one does not merely detect an average value over the totality of all measured neutrons, but the statement applies to each individual neutron. It takes many neutrons to determine the optimal angle of rotation, but as soon as this is set, the path presence determined from it applies to every single neutron detected.
"Our measurement results support classical quantum theory," says Stephan Sponar. "The novelty is that one does not have to resort to unsatisfactory statistical arguments: When measuring a single particle, our experiment shows that it must have taken two paths at the same time and quantifies the respective proportions unambiguously." This rules out alternative interpretations of quantum mechanics that attempt to explain the double-slit experiment with localised particles.
A more technical presentation of the paper can be found here.
Journal Reference:
H. Lemmel et al., Quantifying the presence of a neutron in the paths of an interferometer, Phys. Rev. Research 4, 023075 (2022).
DOI: 10.1103/PhysRevResearch.4.023075
(Score: 0) by Anonymous Coward on Wednesday May 18 2022, @09:50AM (13 children)
Imagine if you simulate the Universe on a computer. The paths are stored in the RAM.
How many states can you store in a superposition? Infinite? How many infinities do you need to store the Universe? Of course as mathematicians will tell you, not all infinities are the same. Go figure.
;)
(Score: 2) by Freeman on Wednesday May 18 2022, @02:15PM (11 children)
The definition of infinity is a number without ending. Which means, given enough time, all infinities are equal. Though, if you start an infinity and then later start a new infinity, one will always be bigger than the other. Except, we generally can't make things that keep going forever. Also, what about something that can count faster than something else? Start one counting 5 years ago, then start one counting now, and given increases in processor speed, etc. One will get to a higher infinite number faster than the 5 year old one. One can say there's an infinite mass, but if the universe isn't expanding, there must be a finite amount of mass. The number is just so mindbogglingly huge, there is no way we could accurately estimate it. Calculating something like that we could be off by the mass of a galaxy or more. Mathematicians are nuts.
Joshua 1:9 "Be strong and of a good courage; be not afraid, neither be thou dismayed: for the Lord thy God is with thee"
(Score: 3, Informative) by Anonymous Coward on Wednesday May 18 2022, @02:47PM (1 child)
By counting, you are already at less than infinity.
Infinity is not something you drive towards; it is an end state.
It's also something that can de defined in more than one way.
Look up Eric Cantor for his work on infinities.
(Score: 0) by Anonymous Coward on Wednesday May 18 2022, @03:16PM
My bad.
Eric Cantor is an American politician.
Georg Cantor is the mathematician you can look up.
(Score: 2) by DannyB on Wednesday May 18 2022, @04:44PM (1 child)
Some infinities are bigger than others. [youtube.com]
The remark about infinities being an end state is insightful.
Fun thing:
What do you get if you add up all of the natural numbers? 1 + 2 + 3 + 4 . . . . . . . . . . to infinity?
The lower I set my standards the more accomplishments I have.
(Score: 1, Informative) by Anonymous Coward on Wednesday May 18 2022, @07:18PM
Misleading. From the article you linked:
(Score: 2) by DannyB on Wednesday May 18 2022, @04:52PM
Another fun thing about infinity. I remember this from college days. I think it was 1979 and some fellow geeks and I were talking about this in the cafeteria in the dorm.
Proof that 0.99999... is equal to 1.
1. Let x = 0.99999.....
2. 10x = 9.99999......
3. Subtract x from 10x.
10x = 9.99999.....
x = 0.99999.....
----------------
9x = 9
4. Divide both sides by 9:
x = 1
The proof works for other things like 0.33333.... being exactly 1/3, etc.
There was one guy who could not accept this. He kept urging the rest of us . . . think in exact terms. The fallacy is that he was thinking of infinity as something you strive towards, rather than the end state.
Maybe the same thing is true about righteousness.
The lower I set my standards the more accomplishments I have.
(Score: 2) by vux984 on Wednesday May 18 2022, @07:16PM
"The definition of infinity is a number without ending."
"Which means, given enough time, all infinities are equal."
Not quite. The most classical example is the difference between a countable infinity and an uncountable one. (One where you can come up with a method of counting the members in the infinite set and one where you can't even do that. The integers are countable, so are the odd numbers, or the negative numbers. Those infinities are the same "size". Even though you might intuitively assume there are more integers than odd integers, you can easily create one-to-one correspondences between all the items in each of those sets. However the real numbers not countable, and which is a property that sets it apart from the other infinite sets I just mentioned, there is no possible one-to-one mapping between elements. The set real numbers is 'bigger'.
"Though, if you start an infinity and then later start a new infinity, one will always be bigger than the other."
Careful. If you start with the empty set and put items in it at some rate, then you have a finite set, not an infinite set. The size of that set is always finite. Yes it's growing over time, and the limit on the size is infinity. But at any given point in time, its a finite set.
"One will get to a higher infinite number faster than the 5 year old one."
It will get to a higher FINITE number faster.
"One can say there's an infinite mass,"
One can say that, but nobody in science believes it to be true of our universe.
"but if the universe isn't expanding, there must be a finite amount of mass."
The universe believed to be expanding, and yes it beleived to have a finite amount of mass*, that is just getting spread ever more thinly.
*Finite but not static, as there are processes to convert mass to energy and back that are taking place. There IS believed to be a static and finite amount of total energy (including energy in the form of mass) in the universe though.
(Score: 3, Interesting) by Immerman on Thursday May 19 2022, @01:33AM (2 children)
>given enough time, all infinities are equal
No. Absolutely not.
First off, there is no "time" involved in infinity - if something is infinite, it's infinite NOW and at all other points in time. E.g. the number of integers never changes. You can try to count them, and at every point in time you will have a definite non-infinite value. But your counting has no effect on the total number that exist - that number is, was, and ever shall be infinite.
Secondly, infinities can have many different magnitudes. As others have pointed out, the number of integers is the same as the number of odd integers - both infinite. But the number of real numbers is vastly larger - in fact as I recall it's been proven that there are more real numbers between 0 and 1 than there are integers.
If all infinities were the same size then inf./inf. would equal 1 - but that is decidedly not the case. The value is undefined precisely because infinities can be different magnitudes, so that inf/inf could be literally anything, including infinity or zero.
A quick and simple example: x=1/v, y=7/v. Both converge to infinity as v approaches 0. But x/y does not converge to 1, as it would if the infinities were equal, instead the v's cancel it converges to 1/7. And that's dealing with the simplest case of two infinities that are the same magnitude.
Ask a mathematician and they tell you that infinity is not actually a number at all - instead it's an abstract concept. Basically shorthand to refer to the limit of anything whose magnitude increases without bound.
(Score: 1, Interesting) by Anonymous Coward on Thursday May 19 2022, @01:25PM (1 child)
If something increases without bound, mathematically speaking, it has no limit. Limits are for things that converge to a number.
(Score: 3, Interesting) by Immerman on Thursday May 19 2022, @03:00PM
I suppose technically you are correct but there's going be disagreement between mathematicians depending on how pedantic they are. Not entirely unlike asking whether 6/2(1+2) equals 1 or 9, which is ambiguous since there is no formal agreement as to whether implied multiplication has a higher priority than explicit multiplication. There seems to be a roughly 50-50 split among distracted mathematicians, and the general consensus when they're paying attention is "don't do that".
The limit of 1/(x*x) as x goes to 0 is a perfectly reasonable mathematical statement. A mathematician may say that the limit goes to infinity, rather than that the limit *is* infinity (since infinity is not a number), but mathematicians are lazy and pretty much everyone will *write* it as "... = infinity" and trust that the reader recognizes the subtle inaccuracy. Some will argue that the limit doesn't exist because of that - but in my experience, unless they're feeling particularly pedantic, they'll generally just stick to providing the more informative answer of infinity and again trust that the reader understands the inherent inaccuracy.
Arguably technically incorrect, but more useful from a practical standpoint as it distinguishes it from, e.g. multi-sided limits where the function converges to different values depending on the direction it's approached from, and thus only exists if the limit also specifies the direction of approach. (e.g the limit of angle(x) as x approaches zero on the complex plane). Or situations where there is literally no meaningful limit of any kind, such as the limit of sin(1/x) as x goes to 0.
(Score: 3, Interesting) by FatPhil on Thursday May 19 2022, @08:04AM (1 child)
There's no definition of "infinity", only the property of being infinite, which all of the various infinities definitionally share, and that is the existence of a bijection between a proper subset and the original set. In layman's terms: you can take elements away and the set remains the same size.
Existence of an infinite set is an axiom which magics one up definitionally with certain useful properties.
There's no process, so there's no ending. Time is irrelevant, there's no "enough" of it, and you conclusion that all infinities are thus real is not just ill-reasoned, it's wrong too, there are many different infinities. Some different infinities have the same number of elements, because number of elements isn't the only property an infinite set has.
However, 150 years ago, if you'd have said any of the above you'd have been considered a madman, and pretty much an outcast in the mathematical community, there was a huge quantum leap between understanding and rejecting it that many were not prepared to make. To this day, a huge proportion of the mathematical cranks out there nowadays are ones that are not prepared to accept Cantor's approach (and who replace it with something not powerful enough to support the claims they make).
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by Freeman on Friday May 20 2022, @01:49PM
I knew there was a reason I noped right out of Computer Science after I finished Calculus I. Though, considering the awfulness of the Business Administration minor that I went through, I may have been happier in Computer Science. The Computer Information Systems degree that I got with Business Administration Minor worked out well enough for me, though.
Joshua 1:9 "Be strong and of a good courage; be not afraid, neither be thou dismayed: for the Lord thy God is with thee"
(Score: 2) by mcgrew on Friday May 20 2022, @01:10AM
Mathematicians have yet to understand the infinite. When they do they'll be able to divide by zero and create a brand new universe.
mcgrewbooks.com mcgrew.info nooze.org
(Score: 2) by inertnet on Wednesday May 18 2022, @09:56AM (6 children)
I'll wait for Even Bananas or Matt O'Dowd to explain it to me on the youtube. They're very good at explaining this stuff.
(Score: 2, Informative) by Anonymous Coward on Wednesday May 18 2022, @10:48AM (1 child)
Might be a while before Matt O'Dowd gets to this one. It's an interesting result but it's not groundbreaking - it just confirms what everybody knows but some people don't want to accept.
Basically they just put another nail in the coffin of pilot wave theory, which was already constrained so much that it didn't really provide any advantages any more. A particle really does travel as a wave. I don't think it says much about whether many worlds or Copenhagen is likely to be correct.
Essentially the normal double slit experiment requires many photons (or electrons or whatever) to reveal the interference pattern. You can only actually observe the photon in one place, so as you measure many photons, they then collectively form the interference pattern.
Here they were able to use the normal statistical approach to define a rule (the alteration of spin) that every particle (neutrons, in this case) must obey. Then they were able to prove that every individual neutron obeyed the rule as it traveled. If the effect were truly statistical and not real, then some of the particles would have been one way and some the other, so it averaged out.
(Score: 2) by Immerman on Thursday May 19 2022, @03:10PM
>Basically they just put another nail in the coffin of pilot wave theory
Have they actually done so? Pilot wave theory still requires that the wave goes through both slits, and then guides the behavior of the particle to be consistent with it having taken both paths as well. I would think that would include imparting a slight but consistent adjustment to its spin.
Last I heard, nobody has managed to put even a single nail in the coffin of pilot wave theory, since the predictions are all identical to those of the Copenhagen Interpretation.
The strongest argument against it is that nobody has yet come up with a pilot wave alternative to the more powerful Quantum Field Theory - but that's hardly surprising given the vastly smaller number of people working on the problem from a pilot wave perspective.
(Score: 2) by Gaaark on Wednesday May 18 2022, @03:15PM
I love Matt O'Dowd. And i could really kill a Cuke right now, then head out to a Sea Parks. Except i'm stuck under this secretaries desk. :(
:P
--- Please remind me if I haven't been civil to you: I'm channeling MDC. ---Gaaark 2.0 ---
(Score: 2) by FatPhil on Thursday May 19 2022, @08:10AM (2 children)
Bananas, definitely not, that's neutrinos only.
More likely is Don Lincoln (who hosts the Even Bananas vids on his channel, perhaps that's who you're thinking of?): https://www.youtube.com/playlist?disable_polymer=true&list=UUD5B6VoXv41fJ-IW8Wrhz9A&ucbcb=1
But most likely is Sabine Hossenfelder: http://backreaction.blogspot.com/ , who reacts to things quicker than most.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by inertnet on Thursday May 19 2022, @09:50AM (1 child)
Agreed, I mentioned Even Bananas in the hope that people here would get curious and look it up. It's likely that many visitors here are subscribed to a number of scientific Youtube channels. I've found a couple by tips given around here, trying to do the same for others.
(Score: 2) by FatPhil on Thursday May 19 2022, @11:23AM
You're thinking of the internet from the 90s.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2, Interesting) by Anonymous Coward on Wednesday May 18 2022, @10:20AM (17 children)
Particles are localized (in space and time) behaviors.
Waves are distributed.
The localized part of the experiment is the instant where the neutron hits the detector.
Otherwise, the neutron exists as a wave.
That would say that the only time we think we know where the neutron is for sure, it isn't a neutron any more.
At the instant it becomes a particle, it ceases to be a neutron.
(Score: 2) by requerdanos on Wednesday May 18 2022, @10:40AM (5 children)
Well, in an interaction such as measurement, it would probably still have to be a neutron in order to conserve baryon number [wikipedia.org].
(Score: 0) by Anonymous Coward on Wednesday May 18 2022, @10:53AM (4 children)
I don't speak neutron, how about photon?
Consider a photon entering a detector.
Before the interaction there is a photon wave.
After, there is an electron raised to a higher energy level.
Where, aside from the instant of the interaction, is there the photon a localized thing?
If it can't be a localized thing without something else to interact with, then how can it be an independent particle?
(Score: 2) by HiThere on Wednesday May 18 2022, @03:35PM (3 children)
And that's why I prefer many-worlds. A photon spreads it's wave front as it travels, and eventually it may encounter something to collapse it. But it may encounter two things that could collapse is separated by sufficient distance that there's no way for it to know whether it has already collapsed. But it's still only supposed to collapse once.
There are other ways to resolve this, like. e.g., superdeterminism, but they seem LESS reasonable to me than does the multi-worlds interpretation.
FWIW, another way to say "multi-worlds" is "the quantum state doesn't collapse", i.e. everything is still a wave after the "encounter", but it's split into ... I don't know the proper word, so ... domains that can't communicate.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 3, Interesting) by FatPhil on Thursday May 19 2022, @08:15AM (2 children)
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by HiThere on Thursday May 19 2022, @01:11PM (1 child)
It could be just what you say, and still be the true explanation (if only we could find the correct evidence). None of the "consistent with the theory" interpretations that I've heard are any better. Do you have a preference? Do you prefer "shut up and calculate"?
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 2) by FatPhil on Friday May 20 2022, @10:42AM
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 3, Interesting) by inertnet on Wednesday May 18 2022, @10:42AM (2 children)
That could work if you imagine one or more extra dimensions, where a neutron is only a particle where it intersects with our spacetime. Anyway, that's how I can envision your comment.
(Score: 0) by Anonymous Coward on Wednesday May 18 2022, @11:14AM (1 child)
Cool, so that would make everything a particle. A wave is just a particle in another dimension.
Probably all this is a case of Feynman was right again. As soon as you think you understand quantum, you're wrong.
(Score: 0) by Anonymous Coward on Thursday May 19 2022, @08:17AM
I've always wondered if our language is part of the problem. Everyone says this or that is a particle or a wave, or that it's a wave that collapses into a particle, or that it's a wave inside a particle, or whatever.
Wouldn't it be clearer if we had a new word for this thing that isn't a particle or wave at all? Because they're not particles or waves, they're something else.
Or is all this already clear to those who at least somewhat understand the actual physics of the thing, but everyone uses the particle/wave talk to try to dumb it down for us knucke-draggers?
(Score: 3, Funny) by pkrasimirov on Wednesday May 18 2022, @10:51AM
Mod +1 Trippy.
(Score: 4, Interesting) by Mojibake Tengu on Wednesday May 18 2022, @12:13PM (3 children)
I strongly agree with parent: the experiment just proved a neutron in a travel through space is not a neutron but something else.
Similarly, if we have a data in computer memory, it's observably localized. Even localised as certain energy configuration, if you look directly on hardware.
But when we are sending this particular data over the network using network packets, the data structure is unbound from its original energy, become seemingly de-localised when traveling, may even travel passing several different detectable paths at the same time.
And re-localised again as data in memory (or configuration of energy) at the destination.
In such transfer, the energy itself was not traveling at all, but the information did.
So, the experiment may indicate the Universe is not just a computer, but a network.
Like this: https://en.wikipedia.org/wiki/Indra%27s_net [wikipedia.org]
For some strange political reasons, this very image inspired by original paintings of calculating spaces by Konrad Zuse https://en.wikipedia.org/wiki/Konrad_Zuse [wikipedia.org]
was removed from Wikipedia's page on Indra's Net:
https://en.wikipedia.org/wiki/File:Indras_Net-02.png [wikipedia.org]
https://en.wikipedia.org/wiki/Avatamsaka_Sutra [wikipedia.org]
Conclusively, it may be very difficult to
hideencrypt something in Universe like ours.BTW, is your favorite encryption algorithm resistant to clairvoyancy?
One such capable observer, Tu Shun, lived 557-640. https://en.wikipedia.org/wiki/Dushun [wikipedia.org]
Respect Authorities. Know your social status. Woke responsibly.
(Score: 2) by requerdanos on Wednesday May 18 2022, @03:38PM (1 child)
Well, no, it's a neutron. That's what, hard as it may be to understand, a neutron is. A smeared-out wavy thing of just probability that only resolves into a "point particle made of three quarks" under conditions like "measurement."
a neutron in travel through space is not a point particle, but then, a neutron isn't always a point particle. Probably hardly ever is, despite how we might think of it.
I see several comments that seem to equate "not a point particle" with "not a neutron" and that doesn't hold: A neutron is what it is, and is a neutron, even when it isn't being a point particle. That's wave-particle duality for you. Quantum mechanics is to common sense as wet is to dry.
(Score: 3, Interesting) by Immerman on Thursday May 19 2022, @03:40PM
>Quantum mechanics is to common sense as wet is to dry.
I disagree - I'd say it's more as aardvarks are to quasars. A.k.a. just not meaningfully comparable.
Insofar as they conflict though, we know that it's common sense that's wrong, since QM is mathematically rigorous and thoroughly confirmed. Though with enough exposure, a particular individual's common sense will begin to integrate the reality, not that it's particularly relevant outside particle physics.
We also have no solid confirmation that "measurements" actually have any significance to quantum mechanics - in fact we don't even have any explanation for what exactly a "measurement" is. E.g. the Many Worlds interpretation says wave function collapse never happens, and it's only some anomaly in our perceptions that makes it seem like they do from our (unexplained) limited perspective. While Pilot Wave theory says the particle was always just a particle, while the corresponding pilot wave never collapses. Since both interpretations are apparently mathematically equivalent to the Copenhagen Interpretation, it would be intellectually dishonest to claim any of them are more or less correct than the others.
To date, the only speculation I've heard that *might* eventually give more weight to the Copenhagen Interpretation is the idea that gravity is fundamentally non-quantum, and thus incapable of existing in a superposition of states. Which would suggest that any superposition of states that increased the gravitational uncertainty of a quantum system beyond some (very low) critical threshold would force the system to collapse into something with a lower gravitational uncertainty - a.k.a. a "measurement" would occur.
(Score: 2) by FatPhil on Friday May 20 2022, @10:46AM
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 3, Insightful) by FatPhil on Thursday May 19 2022, @08:31AM (2 children)
There is no such instant. The interaction is as smeared out over time as the wavefunction of the particle participating in the interaction.
Of course, you have to remember that this is just what the mathematical model of quantum mechanics says, and just because the theory works shockingly brilliantly, doesn't mean it's actually the underlying laws of nature themselves (we already know it produces wrong answers in several situations where we try to use it, so either our inputs are wrong, or the process is wrong, maybe both).
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 0) by Anonymous Coward on Thursday May 19 2022, @11:24AM (1 child)
"There is no such instant." (Or specific place?)
Yes, I was thinking about that in the shower. It's easy to forget that the 'detector' is also a wavy thing and the Shrodinger eqn only descripes the odds of something happening, not what is happening.
Has anybody found a form of equations for what the two things might actualy be doing, that when combined and solved result in the Shrodinger eqn?
(Score: 3, Informative) by Immerman on Thursday May 19 2022, @03:59PM
The closest to a "definite" form of QM I've heard is Pilot Wave theory, which says the particles are actually particles with well defined positions, velocities, and all other properties at all times, while all the quantum weirdness is embedded in the pilot wave with which the particle interacts. In which case there would be a definite and discrete moment of interaction between the two particles.
Of course, from a practical perspective there's not much difference since you've just pushed all the quantum weirdness into the non-local hidden variable(s?) of the pilot wave field(s), and the two particle's pilot waves can interact in a wavy smeared out fashion even if the particles themselves never do.
On the other end of the spectrum you have Many World's theory, which says nothing definite *ever* happens, quantum wavefunctions never actually collapse, and the entire universe is actually in an ever more complex superposition of all possible states that could have emerged since the beginning of time. While the apparent collapse of "measurements" is an (as yet unexplained) perceptual illusion of our awareness, which presumably consists of a near-infinite number of such limited perceptual fragments.
Both are completely mathematically consistent with the Copenhagen Interpretation with which most people are familiar, so we can't really say that any of them are more correct than the others.
The Copenhagan Interpretation has the advantage of being the basis for the more powerful understandings of Quantum Field Theory - but "we've built more on this foundation" isn't a very compelling argument when the other foundations have been almost entirely neglected.
(Score: 2, Interesting) by shrewdsheep on Wednesday May 18 2022, @12:42PM (1 child)
These findings seem to refute De Broglie's theory (https://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory) which assumes that a guide wave (think of immaterial particles) first trace out space to find the inference patterns. Then particles take a specific path following that distribution, meaning they would always go through a single slit in the double slit experiment. Actually, I do not see how the findings in TFA do exclude this possibility. Comments?
(Score: 3, Interesting) by Immerman on Thursday May 19 2022, @04:04PM
I'd need a much better understanding of the experiments (and Pilot wave theory, of which De Broglie's is just one variant) to say anything for sure, but my gut says that since the pilot wave still goes through both slits, and interacts with the magnetic field on one path, it would still guide the neutron in such a fashion as to twist its alignment exactly as though it had traveled both paths itself.
(Score: 0) by Anonymous Coward on Wednesday May 18 2022, @07:57PM
i dunno.
i suppose, "classically" one would first have to ask, when on the flight-path does a particle (here the neutron) "see" that there are two slits and behave accordingly?
another more radical "view" would be to throw out the "ninja" attribute of a experimentor and just assume that the universe is a big brother and "sees" everything (no ninja mode available);
this means it would be like a small bird perched on a tree, ignored by the experimentator, and watching everything faithfully that is going on ... thus the universe is watching the built of the setup.
so anything the experimentator thinks he will "trick" the universe to reveal, is already "old coffee" because the setup is already in existence.
(maybe similar, as how the shape of a surface gives a flow pattern. more radical, the setup of a machine/experiment yields a predetermined result)
the "coloring" of a split flight path is rather clever, but the "randomness" cannot be guaranteed. a better(?) way would be to let "schroedingers cat" determine if a rotation/coloring is applied or not.
the decay can be measured and can be the signal to rotate or not. so the bird on the tree "sees" the setup but what will it yield since a unpredictable (but with a known decay rate) element is introduced?
will it fly? will it crash?
(Score: 2) by mcgrew on Friday May 20 2022, @01:07AM
The last panel always cracked me up.
https://www.angryflower.com/387.html [angryflower.com]
mcgrewbooks.com mcgrew.info nooze.org
(Score: 3, Interesting) by loki on Friday May 20 2022, @01:09AM
How clear is it that time flows in only one direction at the quark level of reality?
Statements like "it must have taken two paths at the same time" assert things not only about space but also time.
Did they actually test that there was no time-reversal at the atomic level?
At the quark level, time may not be as simple and one-way as at our level of reality.