When physics teachers try to explain rudimentary quantum mechanics, such as the two-slit experiment, they say you can visualise it as particles for some purposes but as waves for others.
Apparently, there's a splendid way of helping you visualise that actually it's both - with a simple practical experiment:
We Built It, But They Didn't Come....
2 hours ago
8 comments:
Nothing I need more on a Saturday afternoon.
Not tiny men in oil-stained overalls?
Quantum mechanics does not refer to physical objects. Electrons and photons are not physical objcts. Quantum mechanics is a mathematical schema used to to make useful predictions about matter and electromagnetic phenomeona.
@Dinero
I thought he made that very point rather well; I understood him to be saying clearly (I'm paraphrasing) that we weren't dealing with quantum objects, merely something in our bit of reality that showed similar "behaviours" to the largely inexplicable in another bit of reality and that it might be useful in visualising what's going on.
And as an official Old Fart, may I say how deeply jealous I am of these young men and women particularly in the STEM disciplines who have good looks, charm, knowledge, confidence, fluency, and most of all intelligence. Bastards. Where's my cup of tea.....
Very good post. Thanks Mark. I agree with Formertory on this one (including the second paragraph with a cuppa :).
Nevertheless I am left feeling uplifted by the neatness of how they find solutions to the toughest problem and then communicate the problem/solution by powerful Argument from Analogy. I have no comment on where they are at the conclusion of the presentation and how you would select between intepretations. Completely beyond my paygrade, but my earlier (longstanding) philosophical puzzlement has been lifted.
After putting down my cuppa, and thinking aloud about what interested me most about the slit experiment problem in the first place: could one argue that some Social Sciences, in putting their faith mostly in Argument from Ideal Type model, in fact, miss one of the key tools above, actually progressing the Physics they have sought to copy in some other respects?
JH, all part of the service.
S, sadly not.
Din, exactly, in the experiment, the "particles" and the "waves" are both made out of the same substance.
The real weakness is that the experiment merely illustrates in 2 dimensions, which is find for something like two-slits which still makes sense if viewed from above as if it were 2 dimensional. In real life, the particles and waves move in 3 (or more) dimensions.
FT, thanks for back up, my thoughts entirely.
MW, weakness of social sciences is they have to reduce the number of dimensions and ignore things inter-acting with themselves, for example self-fulfilling prophecies, see also second part of my reply to Din.
Though the theory has utility in the economic world which is great and lucky, the actuality is still not understood at all. So what? Well you could say the same about God creating the world 4000 years ago right? No fundamental difference in utility or reality.
Same with galactic core black holes of a thousand billion solar masses concentrated into an infinitesimal point, dark matter and dark energy to fudge old numbers that no longer stack up with new observation and then keep changing the factors to suit, or that the universe expands faster the further away it is and then the best we get is to declare its another multiverse attracting us. The best one is where we see the latest picture of an atom which looks just like another blobby thing and then to rejoice that an atom is truth, look we have proof.
Science at its best is utter Christian scientific religiosity nonsense. Not a surprise given the enlightenment was led at inception by the devout wanting to use science to prove that God is real and gradually that image becoming normalised over the next 300 years so we're no longer aware of the fantasy. Its purveyors are the modern day high priests. Not necessarily a bad thing, but maybe, it's down to fate as to how we'll fare unless we're bold enough to drop all beliefs and then, look at what something really is without that master informant guiding us.
Same with galactic core black holes of a thousand billion solar masses concentrated into an infinitesimal point, dark matter and dark energy to fudge old numbers that no longer stack up with new observation and then keep changing the factors to suit, or that the universe expands faster the further away it is and then the best we get is to declare its another multiverse attracting us. The best one is where we see the latest picture of an atom which looks just like another blobby thing and then to rejoice that an atom is truth, look we have proof.
I may be missing your point but don't think there's much point decrying changes to theory as fudging; surely it's just the way that the human race has developed its knowledge and understanding (as imperfect as it may yet be in many regards) from the outset: Look at something. Develop a rationale for what's seen; the rationale is informed by one's existing "knowledge" and experience (and especially in the case of matters religious, by local personal political advantage, too). If it works, fine. If later observation or experience shows it doesn't work as well any more, change some assumptions until the model works; rinse and repeat as necessary. Sooner or later there's a breakthrough moment which fundamentally rewrites everything, for a while.
The Catholic church and the geocentric solar system. Phlogiston theory. How sexual reproduction and inheritance works. All the answers seemed reasonable and right at points in history until other insights showed them completely wrong-headed. AI systems / neural networks surely work in much the same way? Learning by mistakes, managing exceptions.
Arthur C Clarke's Three Laws sum it up neatly (of course):
(1) When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
(2) The only way of discovering the limits of the possible is to venture a little way past them into the impossible.
(3) Any sufficiently advanced technology is indistinguishable from magic.
It's the last one that's the killer. It allows for completely outrageous theory based on the knowledge of one's own informational deficit. With the sum of human knowledge doubling every few years (and showing signs of doing it more and more quickly) then in a few hundred years time, the science of that time will be (to us, here and now) indistinguishable from magic. In a few thousand years, perhaps we'll be indistinguishable from gods. Big trick is staying alive that long!
I haven't seen the video you linked to yet, but I see it's from 1979. Should be interesting.
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