The hallmark for any reinterpretation of QM in terms of more classical ideas would be that it explains Planck's constant in terms of other constants. If an explanation of a quantum phenomena succeeds to eliminate one of the fundamental constants, all physicists will provide a listening ear, no conspiracy involved...
Double Slit Experiment No Mystery
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Re: Double Slit Experiment No Mystery
#22The wave/particle duality notion isn't really meant to hold an accurate deep insight into QM, it's just meant to inform intuitions, and sorta communicate it to laypeople.
This is not correct. The duality is the fact that an elementary particle is point-like but requires wave mechanics to describe its motion. Another related discovery was that energy waves, too, consist of quanta, which in many respects behave as particles. Those are valuable physical insights (similar in its power to the idea that “everything consists of atoms”).
Re: Double Slit Experiment No Mystery
#23With respect I simply disagree with Feynman that the double slit experiment contains everything... Maybe in suggestive outline?
As an example of how QM is weird, my go-to is a game that I call Betrayal. It is a challenge for a 3 person team. The teammates go through rounds where they are relativistically separated and unable to talk with each other; each such room has a big computer screen and two buttons labeled 0 and 1, and during each round each teammate has to press one or the other of these buttons; then their selections are summed up to a number that we call The Sum.
The reason we call this Betrayal is that we are trying to force one of the teammates to betray the other two. So 25% of the time we run a “control round” where we ask everyone to make The Sum even, and the team passes the round if The Sum is even. Or the rest of the time we secretly select one of the three at random to betray their colleagues: we tell the other two the true goal, make The Sum odd, and the team passes the round only if it is odd: but we lie to the traitor and tell them to make The Sum even, so they will work at cross purposes to the other two.
The key result is that there are 4 cases and classical strategies can only work for at most 3 of them, so your pass rate is limited to 75%. But quantum players who share a so-called “GHZ state” can pass 100% of trials in principle—albeit quantum computers have finite probabilities of simply failing, but if you could improve that to 90% fidelity then over the course of 100 rounds you will still score visibly ahead of the 75s, occasional 80s, and rare 85s produced by random chance.
The key is that quantum systems come out with these strange global correlations that cannot be explained classically. You also cannot see them locally; nobody knows the round succeeded until everyone comes back together to compare what bits everyone committed to.
Re: Double Slit Experiment No Mystery
#24When I watched a goofy layman’s explanation[1] about the double slit, it stressed the importance of the effects of observation on the behavior or nature of the electrons. When observed to see “which” slit the light passed through, they no longer created the interference pattern described by Duane’s law. And when left unobserved (at the slits) the interference pattern emerged even when shooting “one electron at a time…
The focus on “observation” in quantum mechanics is dumb and damaging. In quantum mechanics observation means something very different from what people assume when you use the word observation. When you say “if we observe the position of the electron” people think: “we put an observer who without interring in any active way and he looked at the electron to see where it is”. What QM actually means is more akin to “if w…
Observation is what makes physics matter in the practical sense.
Re: Double Slit Experiment No Mystery
#25This explanation doesn't seem to leave any room for the experimental observation that simply knowing which slit the electron went through - not some physical interaction that disturbs it but simply having that knowledge - changes the pattern.
How would you know which slit the particle went through without physically interacting with it?
You can decide afterwards whether to figure out which way it went or not, and make your observation then. While the English language isn't great at describing this sort of thing, it seems fairly safe to suggest that I cannot choose now to physically interact with an event that happened in the past.
Re: Double Slit Experiment No Mystery
#26It is very common in physics that the same phenomenon can be explained using different concepts. Treating particles hitting a regular structure as diffraction of de Broglie waves gives exactly the same results as the momentum transfer approach the author prefers. In fact, both can be derived from standard quantum mechanics and both are widely used, depending on which is easier in the particular case. However, scatter…
+1 for the delayed choice quantum eraser as being the one experiment that makes it more or less impossible to argue against quantum weirdness.
Re: Double Slit Experiment No Mystery
#27I'm a physicist and I'm sorry to say this blogpost is just drivel (I'm sure the original works linked are perfectly fine).
Re: Double Slit Experiment No Mystery
#281. It’s very nice to be introduced to Landé and Duane. 2. After so much emphasis on reason and experiment and evidence, it is jarring to switch gears to a conspiracy theory about scientists concealing or ignoring theories in order to make themselves seem “superhuman.” 3. It’s very nice to be introduced to Landé and Duane.
You'd be surprised how much scientists hush and push dissenting voices which don't suite a particular theory which one cabal wants to be true. Sean Caroll has been advocating strongly in public to go back and take a look at measurement problem but nobody wants to do it. He speaks more about this on his podcast (mindscape) and also on Joe Rogans podcast ( I mean the fact that he had to bring it up in Joe Rogans podcast to let the public know what's up) is pretty bizzare and in indicative of the kind of schemes that go on in academia.
Re: Double Slit Experiment No Mystery
#29Earlier quoted context omitted.
How can a "thought experiment" demonstrate anything?
Well, from the article on the dual-slit experiment ... > What many don’t realize is that the double slit experiment (with particles), proposed by Feynman in 1963, was for decades only a thought experiment. Finally, in 2013, it was successfully performed with electrons.
The author implied it was a thought experiment for "particles" like electron, though actually demonstrated from the very beginning for non-particles such as photons.
That claim still might not be true.
Re: Double Slit Experiment No Mystery
#30Actually the mysteries are deeper. This one can't explain "Delayed Choice Quantum Erasure" experiments, which is also a double slit experiment. But the arrangement allows you to detect the path AFTER the photon has traveled through one of the slits and hit the surface. Now after the photon has hit the surface you can decide whether to detect its path or not. A delayed choice. But based on your later choice the interf…
How can a "thought experiment" demonstrate anything?
All mathematical proofs are thought experiments, for starters. Similarly, all predictive output of scientific models is technically thought experiments, although we nowadays use computers to achieve superhuman precision and accuracy.