I think that it may be more related to the observation machine causing an electromagnetic interference rather than observation in general. As for what it means, I think I need to learn research more before I can draw conclusions
People focus on the “does it pass through one slit, or the other, or BOTH?” thing too much.
Consider the single slit. There’s an interference pattern associated with the single slit, the width of which varies inversely with the slit width (this is true whether you use photons or electrons. And, for the double-slit case, the intensity of this diffraction pattern acts as the 'envelope" for the much finer double-slit pattern. This is usually ignored in freshmen portrayals of the experiment). If I make the slit wider, the overall pattern gets narrower.If I make the slit narrower, the pattern gets wider.
there’s no doubt that the photon/electron passed through that slit. The question is How does it know how wide the slit is? Just as with the double slit experiment, you can filter the light (or electron source) down to the point where you can be sure that only one particle at a time is passing through. So the probability of a particle going to any point in the long run follows the expected probability for that slit width. But the slit’s clearly a lot wider than you’d think a photon ought to be, or than the txtbook says an electron is. You’re forced to conclude that, although the particle may be small, its influence extends out much farther. If that’s true for a single slit, it is just as clear for a double slit.
how about a triple slit? The diffraction pattern for a triple slit is different from a double slit, or a single slit (although the single slit pattern still acts as an ‘envelope’ for the pattern). It’s absurd to ask which slit the particle goes through – by the statistics of the resulting diffraction pattern, the particle clearly “knows” that there are three slits, rather than two, because the pattern is different. It’s pointless to say “which of the three slits did it go through?” Clearly, in some sense, it went through all three.
The pattern for four slits is different from that for one, two, or three slits.
…and so on, until you get to a diffraction grating, and have a huge number of slits.
Extra mind-blowing credit: What happens if you have two slits of different width?
Answer – you get a pattern with the same spacing of lines, but with an “envelope” function that doesn’t look like that of either of the individual slits. Again, you can filter the flux down until you’re certain that you only have one particle at a time going through. The fact that the envelope function doesn’t look like either slit alone tells you that the particle somehow senses both slits simultaneously.
You can play all sorts of games like this. Cover one of the slits with a polarization rotator and send polarized light in. You won’t see the kind of two-slit pattern you saw before, but if you use a polarization sensitive detector you’ll see the polarization of the pattern varying along its width.
Conclusion: The photon (or electron) doesn’t conveniently fit your mental image as a tiny billiard ball of stuff that has to pass through one hole or the other. It’s more like a tiny dust bunny with a long exponential fringe that extends out quite a distance to pick up the effects of physical barriers very far away from its “center”. Or else light is a wave phenomenon that obeys the Fresnel-Huygens principle of regenerating itself from every point on the wavefront. (This works for electrons and other particles, too) Neither model is an exact representation of the reality, but either lets you visualizethe situation and explain aspects of its physical behavior.
In the tradition of Cecil answering even the stupidest of questions, I’ll briefly explain. As you might infer from other Doper responses, both are fully worthy of being sumarily disregarded.
What The Bleep starts with the valid notion that we don’t yet fully understand quantum mechanics or the locus of conciousness within the brain. Its leaps of “logic” thereafter are like a bunny rabbit in a trampoline store, quickly spouting made-up spiritualism drivel while still pretending it’s science. It’s the mystic equivilent of “don’t know, therefore: God.”
The Secret and its ilk (Abraham-Hicks is the same thing) is pure, unadulterated bullshit that I’m surprised anyone with a functioning braincell can’t see through. An entire book, with sequels and spinoffs, and a movie, and a greeting card line, all can be summed up as, “to get something, just want it really, really really hard.” It’s prayer without a deity. It’s a laughable and transparent money grab.
Both share one important aspect that circles back to the double slit experiement. Neither can produce repeatable experiments. That’s what’s so wonderful about the double slit setup: you can perform it, even at home, with simple materials, and the experiment results in the same result every time. When real life science experiments, others besides the first scientist can repeat the setup and get the same results. The bullshit psuedoscience of quantum spiritualism doesn’t produce controlled experiments at all, let alone repeatable ones.
We have brilliant physicists and mathematicians working every day to decifer the weird properties of quantum mechanics to learn the whys and how’s of the universe. The mystics you need to ignore are either swindlers or they start reading Brian Greene, can’t understand it, and somehow conclude that changing a down quark in their brain to an up quark will get them that bicycle or cure their cancer
Well, I kinda thought that’s what this thread might have been about. 