Double Slit Experiment

[Stevo]

Found this on youtube.

Enjoy

Steve

[JamesF]

I can cope with the idea of wave/particle duality. I don't understand it, but I can cope with it. It's the fact that an apparently passive observer can cause the outcome to change that I struggle to get my head around. Not only is the world weirder than we think. Sometimes it's weirder than we *can* think.

James

[George Jones]

A Do-It-Yourself Quantum Eraser: Scientific American

A Do-It-Yourself Quantum Eraser: Scientific American Slideshows

[evilgeenius]

It's a great video but it's slightly misleading as the eyeball in the video is not a passive observer. In order to observe something you need to have an interaction with it. So you can never observe something without having some kind of an effect on the experiment, it's literally impossible.

[ollypenrice]

I suspect that time is the culprit. We think we are sending 'one photon at once' because, in our perception of time, that is what we are doing. But what if our perception of linear, tensed time is wrong, or not applicable to the waves/particles under observation? Time took one big intellectual body blow early in the last century and I wouldn't be at all surprized to see it take a few more.

Olly

[DarkStar7]

I'm on tricky ground but...I'm going to state that..

Any subatomic particle that is in the same quantum state as another particle of the same type is one and same particle!

In Quantum physics two particles may be entangled with one another and when seperated over large distances.. even seperated over the distance of many lightyears one person can deduce the quantum state of another.

I'd like to explain a new hypothesis I came up today...lol so you guys can shoot me down in flames if you can.

I believed up to now that whereever you look around you no matter what direction you look, if you pick any object and you zoom way way down towards an infinetessimal small point you would reach the same point no matter if you had chosen another object. I believed that all infinitesimal points were joined together. This I thought was how entanglement worked and it has helped develop some good ideas for me. It seemed to work well with the photon that was effectively zero size but I was at a loss to explain the electron.

Now I propose that any particle that is in the same quantum state is one and the same particle.

If you fire of a stream of electrons that are of the same quantum state they are all the very same particle seen from different perspectives. Even electons elsewhere in the universe if they are the same quantum state it is still the same particle. At this point distance is an illusion.. there is no distance between them! at least in the quantum world. With one electon in this state there are virtually almost limitless locations where it could be viewed in the universe yet it never really moved it's still in the same place. When the electron becomes entangled with another in a different state, the number of locations where this duplicated is rapidly diminished. There may still be many locations in the universe where two electrons with two different sets of quantum states combined exist... but not so many. If three different particles with their combined quantum states are combined the combination of quantum states is so rare that the group can only exist in perhaps one location. It becomes more real.

Lets look at the double slit experiment again;

Source A fires a beam of electrons at screen B. We can look at the group as one large spead out particle that moves through both slits at the same time. Any measurement will change the quantum state of the electron and the number of locations in the universe with the combined quantum state of the electron and that particle that done the measuring will be greatly diminished. Viewed at that location it now becomes seperated and becomes unique to that location, and only goes through one slit.

I don't expect to be taken seriously so be kind

[evilgeenius]

Keep smokin' that cheeba..

[DarkStar7]

Have I lost touch with reality then? lol

At least still I know the answer to life the universe and everything is 42. ...it is isn't it?

Seriously, wouldn't it be great if some solved this quantum weirdness.

[DarkStar7]

What I should have added to what I said on my crazy first post on this thread is that in the two slit experiment the spread out photon or electron to me, before it is disturbed looks like a point that is blurred out and kind of out of focus, as we percieve it at our scale. If we zoomed towards it, towards infinitesimal small scales we would end up at a position which is where you could have a distortred view all the other possible positions where the electron can be observed ... Like being under water and looking back up at the surface, at this point you would be at the very centre of the electron, you could then choose the direction to travel back up towards larger scales and reappear elsewhere.The distance between the start of the journey and the end is very short. Unfortunately you could not do the journey without passing through the centre of the electron or what ever the particle is and disurbing it.

If you were a travelling particle, and was very careful on the journey ie like having a simple quantum state the best you could achieve is that once you approach the centre of the electron to be measured and looked back up at up towards larger scales, you could still see a distorted view of all the positions in the universe that contain the combined quantum states of both you and the electron.. quite a low probability though

[toml42]

Darkstar, the problem with your hypothesis is that interference still occurs even if you fire your photons or electrons one at a time - individual particles seem to posses the ability to interfere with themselves.

For all intents and purposes we've already 'solved' the quantum weirdness, quantum theory is one of the most accurate to date - even though our brains may never be able to fully grasp why!

[Macavity]

I recall someone once (Feynman?) saying that most Physics (post) graduates never really understand quantum theory? Perhaps too, the first twenty pages of the typical AQM text book, including a (rather incomprehensible!) description of the Double Slit experiment? <G> But it does not stop them mastering their studies, conducting valuable research, writing papers etc. Science needs enthusiasts, able grafters etc.

'Course, no problem, if you really DO (as some) understand such things.

A professorship (or several), research funding, (BBC series?) beckons...

[toml42]

"I think I can safely say that nobody understands quantum mechanics." - Richard Feynman

[Space Bat]

At least still I know the answer to life the universe and everything is 42. ...it is isn't it?

I have reached the grand old age of 42 and still haven't got a scoobies to the meaning of life

[JulianO]

Those who are not shocked when they first come across quantum theory cannot possibly have understood it. --Niels Bohr.