Wave Function Collapse

[dzsquared1]

I have developed a logical explanation for wave function collapse, but I'm not smart enough to understand it.

[norakat]

I've heard of this experiment many times, but is there an actual video demonstration that shows this wave collapse in real-time? I would like to see it happen for myself.

[makeithappen42zx]

The wave function collapse gives Dr.Quantum a h@rd on.

[Kaeralho]

it's not about observing, it's about MEASURING.

to measure, you need to bounce off a photon on the particle, which changes the momentum of the particle. so you know where it was, not where it is now, for you changed it's trajectory.

[fateswarm1]

I fucking hate this character.

[ciavarella1292]

*MIND FUCK*



[TheisticThinker]

This is very very interesting. How does the electron 'know' when it is being observed? What is the mechanism which drives it to behave differently just by a observer looking closlely?

[powpanda]

@TheisticThinker I believe it must be struck by a photon light particle in order to be observed. but the size of a photon is comparable to the size of the electron. so when you observe it you actually affect it significantly.

[YARTES2K8]

The act of measuring affects the interference pattern.

[D1kk0p]

The world isn't what it seems to be. Your brain tells itself the particles go through and mystically make a wave, but in fact, everything you see is a 'wave'. When we look, our eyes perceive the matter as if it's acting 'normal', but that's because our brain tells our eyes this is how it's supposed to look. We need to see a physical world because else we can't understand. How far away are objects actually? We can measure it with our eyes and brain. But what if distances are just an illusion...

[zurechtweiser]

Wave functions are not simple to really understand. I do, but not by watching this video. By putting an ugly, badly animated character into the scene and making it sound like being pseudo-enthusiastic it does not become easier.

[Godlessmass]

If this vid piqued your interest in the particle/wave duality, visit this youtube vid: v=x5RQ3QF9GGI It's also a layman's explanation of the 2-slit experiment, but it's a bit more robust and the lecturer explains why the introduction of an observer changed the result. I.E. there's no mystical reason, our tools just aren't delicate enough to make such an observation without breaking the experiment (and as far as we know, we cannot make tools delicate enough to do so).

[moneybeans]

From my understanding, this is a pretty mystifying explanation of what happens. The freaky giant eyeball in this video should have a flashlight above it. Electrons act differently when observed because light FROM the observer pushes them.

This is the crux of the uncertainty principal. Because the act of observing PHYSICALLY (not mystically as depicted in the video) interferes with our experiments, it's impossible to know the exact position of any object.

[FeedMoi]

WTF? so it just changed because it was being watched??

[sunstarangel]

I had a college professor that explained it the same way that this video did... and said it was way beyond most of the scientists as to why this wave function collapse would happen when observed. A mystery.

[walt776]

There is real science behind this, but don't trust this movie. It was funded by a New Age cult that distorts scientific theory to fit its non-scientific fantasy belief system.

[tcsrinivasan]

since electrons act as a wave when not observed at quantum level what would be the state at classical level .

[2tame4fame]

So we went from looking at large particles, to atoms, to subatomic particles and we realized they are waves. So the building blocks of matter are somehow just a function of certain waves. Hence the string theory. We are matter hence when we observe this building blocks of matter we force them to show up like particles. Thats how I understand it. So we are lucky that we observed these particles behaving like waves, because thats what they are. Looking deeper (strings, etc) will be v difficult.

[2tame4fame]

The particle is the expression of a function of the wave. NOT the other way around. The electron and other subatomic particles (the universe and the whole reality including humans also) are just a function of this wave(s). That's why when we look at it, it appears as a particle. We are observing one effect of the wave (matter) so when we try to pinpoint it we only see its function (manifestation) as a particle. We after all are matter hence included in the same function of this waves.

[johny260]

the measureing device changes the electrons properties because it has to interact with it to measure it. so the measuring device simply changes the property of the electron from acting like a wave to acting like matter since it can act like either. How does that violate known physics?

[ubalup]

if a cow observed it would change?

if a bug observed would there be a change?

if a rock observed would the outcome be difference?

[LapisGarter]

How do we know our method of measuring isn't affecting the outcome?

[TriKri]

Who performed this experiment? Where can I read about it? I think it's strange that it's not investigated further, unless the video leaves that out of course.

[TakesTwoToTango]

@TriKri Of course it's investigated further. The video is wrong too as far as my quantum mechanics classes go... There was no little eye observing the electrons as they went through either slit, they closed one slit off, which is in fact observing which slit it went through. When they did that (which is a DIFFERENT experiment!), they didn't get an interference pattern, but a probability distribution of where the electron was that is consistent with classical physics.

[TakesTwoToTango]

(continued) This is to be expected, because if in limit cases quantum mechanics would NOT predict the observation that are observed by classical physics, then it must be wrong because those observations ARE there and are made. I'd check university textbooks if you want to understand scientific experiments. This is the double slit experiment by Thomas Young. The English wikipedia is very good for quantum mechanics if you want to look into it :)

[TriKri]

@TakesTwoToTango Well THAT'S bad in that case; if you're closing one slit off, of course you won't get any interference pattern... :( I'm actually studying quantum mechanics right now so I don't think that is necessary, but thank you anyway :)

I watched another Dr. Quantum video too about quantum entanglement, which made it seem like information could be sent quicker than the speed of light by affecting one object entangled to another; something that later turned out to be completely incorrect.

[chrisofnottingham]

High production value video, generally good explanation of QM expts but misleading in several key ways.

Electrons do not leave as particles, split into waves, then recombine into particles. They travel as a wave function until they are collapsed by the screen or the detector.

5:05 "waves of what?" probability (broadly speaking).

As I understand it the collapse is due to a transfer of information and doesn't need a person.

[angelsssssssssssss]

50/50 chance of cohering ( Appear and become a reality) and the other quantum wave function decohering (Vanish).

[angelsssssssssssss]

In my personal opinion, I disagree with Bohr's interpretation of Schrodinger's Cat. He claims that when the cat is in the box unobserved, the cat is truly alive and dead at the same time, but when you open the box and observed it yourself, one of the cat's 2 quantum wave function of being alive and dead decoheres (Vanish) and the other coheres (Appears and become a reality.). Well, I believe that the cat is not alive and dead at the same time, but the 2 quantum wave function have a (Continue)

[Rockstafeller]

@angelsssssssssssss exactly, i completely dont understand how they arrived at this conclusiion, it simply shows lack in our perception, but doesnt mean that the cat is actually dead and alive at the same time, please...

[angelsssssssssssss]

@Rockstafeller I know huh. I have no idea where Bohr came up with this subjective idea of the cat being alive and dead at the same time. To me, it doesn't make any logical sense. Albert Einstein also disagreed and hated Bohr's paradox of the cat. Yes, any object can be in multiple quantum levels at the same time, but the time it could be there depends on Planck's scale divided by the gravitational self energy.

[mssharpie]

yes.but to WHICH educated person do i listen to? one physicist says one thing.another says some thing else.

[3rdeye7thdimension]

If you say you understand quantum physics... you don't understand quantum physics.

[sdegan85]

What they say seems true if you believe in the Copenhagen Interpretation of QM. What they don't tell you is that this is all based upon mathematics, which is a tricky philosophical departure from reality. When they say observe, they mean "operate on an eigenfunction in order to collapse the wave function in order to get an eigenvalue." This is VERY simple mathematics. But you have to remember, it's just that. - Math

Extinent: Get an education. Until then, listen to what the educated say.

[murdocha]

I think what is happening here is a misinterpretation of the word "observe". It is not the act of observation that collapses the wave function, it is the testing. Keep in mind this is happening in the quantum, the incredibly small, it does not transpose to the macro world. As much as one would wish to influence the outcome by positive thinking, it doesn't happen.

[extinent]

is that what they told you in in your institutionalized one way thinking PHD MASTERS course or did you fire up your particle accelerator and have look ?  it does happen according to doctors I should be dead but I changed how I felt about that situation and happen to feel much better. and yes it is an interaction with the observer ...all conciseness is allowed to change its mind

[murdocha]

No, it's how quantum physics work. Perhaps before you pick and choose scientific terms to fit you ideas, you should learn them first. And proper spelling would help as well.

[uhmgaige]

So if a blind man were to observe, would the results change???

[tinystories]

@uhmgaige how exactly does a blind man 'observe'

[THEPONCH88]

@uhmgaige -i dont think it would really matter though because he wouldnt see it and anyone watching what he is seeing, has their own perception, maybe? i dont know haha

[Godlessmass]

@THEPONCH88 The explanation in this video isn't complete. How do you observe something as small as an electron? Physicists shined light at the electrons and recorded when the light's path was altered by an electron. Unfortunately, the photons aren't altered unless they strike the electron, which changes the path of the electron. Basically, electrons are too small to be observed without changing the experiment-- so the different results aren't as mysterious as this video suggests.

[BrennFilmcom]

@uhmgaige Observing at that level means first hitting it with photons so you could 'see' a result. That 'hitting' means it changes the electron. It's like a radar gun for measuring speed. The shoot photons at a car: no change. Now try shooting a car with elephants. That would have the same impact as shooting electrons with photons.

[bizzyb1999]

@BrennFilmcom But then why would it be so consistent? It seems strange that the interaction with photons would take the electron from wave like behavior, to what looks like a single electron. If it were the photons causing the change, there would be varied results I'd imagine, but if you could delineate further, that would be nice.

[BrennFilmcom]

@bizzyb1999 First... NO ONE knows exactly WHY this happens. Even Richard Feynman said, "If some one says he understands, he doesn't. I don't even understand, but this is how things work. If you don't like it... go somewhere else".

In this case it would have something to do with Heizenberg uncertainty principle. You can't know where an electron is and it's momentum. This gives an electron the possibility to be at more than one place AT ONCE. Very counter intuitive but this experiment proofs that.

[bizzyb1999]

@BrennFilmcom Ah yes, I thought you were using the interaction with photons as an explanation of why the electron reduces to a single state when under observance.

[BrennFilmcom]

@bizzyb1999 I know I used the Elephant metaphor incorrectly but it satisfies most. Most... but not all :)

This whole Quantum stuff to me is almost spiritual. If you think about it... we are made out of tiny packets of energy, so small it's practically nothing and yet, it gives us mass, substance and thought. If you could pack all your atoms in your body together, without the free space in between, you would not be bigger then the width of a human hair.

[arshsingh1984]

I like this explanation in layman's terms of the wave function collapse; but I don't like Q's abooga-booga implications

[alienrobotmonkey]

wave functions always collapse in the mind via the grey matter

[whiterabit998]

WHAT IF

some how the atoms knew? what if they are actually forms of life, just too small for us to observe? what if they live on a whole smaller level of existence?

[xlovenuggetx]

i know what you're saying.

atoms are life.

we are them. they are us. we have to remember that DNA and life self-assembled.

uncertainty is a bitch though.

[bhn45r]

what is life? Consciousness? Then the answer would be yes.

[Pudersepp]

Then they would have their own small world which would have their own small microscopic elements. This is something proposed by the Greek, the atomos. Perhaps it has more to do with energy, not the conscious world.

[alexxanderos]

Sorry to fight your imagination, but the only reason they acted how they did when observed is that there is a physical interaction when we observer something. Photons have momentum, and they bounce off of material and atoms, to our eyes where we interpret them as color and objects. If the atom is small enough, like and electron, the momentum is enough to change the intended path, and make it assume a matter-like object.

[vne1233]

@alexxanderos

well, photons don't have momentum, electrons are not atoms and particles have no 'intention'. the rest of your comment doesn't seem to make sense at all!

you are right though to point out that 'observation' here is just a kind of physical interaction, the wave function is collapsed by an interaction with a sensor at the slit just as it is collapsed by the board at the end when it hits. the videos implication of the intent and purpose of observation as significant is misleading.

[senor47]

True. This is pretty cool stuff. Just observing changes the outcome.

[cycla]

Wave function collapse has never been proven, merely an appearance like that of tachyons.

[xxkrsxx]

if the act of measuring disturbs the experiment than how could the theory ever be proven? you have to look at it deeper than a proving theory or solving an equation.

[cycla]

then talking about this makes no sense if our logical foundation is built on false premises. How do you suggest that we should understand the issue of quantum uncertainty?

[bellibulle1]

I think the atoms were not observed during the experiment, but the result was.

[ivan3x]

this is like a joke ! I was waiting for continue but it ends :S

[laurenticwave]

horribly coy delivery by the narrator, but the info and graphics are first rate.

[Ramanujan88]

Wish they teach us this in school!

[willingtorisk]

Can't, they need our minds closed, unquestioning. It makes the educational system look foolish as it teaches and demands authoritatively.

[vne1233]

@willingtorisk

the reason they don't teach people this in school is that most people won't understand it, will make false assumptions and come to false conclusions, just like most of the people responding to this video. do you understand it? most probably don't but many of them might think they do, a way of thinking which a school shouldn't encourage. also they tend to teach more practical physics relevent on the macro level in school. more relevent to any science related jobs most might get.:)

[Ramanujan88]

BOTH/NEITHER...oh, it's all so awesome!