Double Slit Experiment No Mystery

I absolutely agree. We tend to forget that nothing is still in our universe.

Everything to the smallest quanta oscillates. The only way to get something to stop moving is by freezing it. You need to hit absolute zero to stop movement completely, I don't believe we have even observed absolute zero.

If you think about it, absolute zero shouldn't be possible. There are an infinite amount of degrees between 1 and 0. Aren't we only limited by the sensitivity of our equipment?

Physicist here. This is just self-congratulatory nonsense. Though I shouldn't be surprised, because I originally signed up for this site to comment against some other self-congratulatory nonsense.

Quantum mechanics is built on extraordinarily simple rules, in fact simpler ones than classical mechanics: all you do is sum up the amplitudes for various paths, and square it to get a probability. The problem is that the objects obeying these rules thus act neither like particles nor waves. So obsessing over whether quantum objects are "really" particles or waves is not useful.

It certainly works sometimes. There are many limits where quantum objects behave just like particles, or just like waves (there must be, since we must be able to recover classical mechanics from quantum mechanics). And sometimes you can describe a quantum calculation in terms of classical wave or particle intuition, which is what's going on here. The double slit experiment is in fact so simple that I know of at least 5 ways to derive the result, using all sorts of different intuition. "Duane's law" is one of them, though I never knew it had a name, as it pops out rather straightforwardly from the mathematics.

The reason that we don't try to extend this to cover all of quantum mechanics is because it doesn't work. Treating the quantum mechanics as if it were classical underneath leads to all kinds of paradoxes. Bell inequality violations tell us that the classical variables would have to either influence each other faster than light, or be pre-set since the beginning of the universe in a malicious conspiracy. The delayed choice quantum eraser tells us that if you want to treat the photon as a classical particle, you need to accept that it can retroactively change the past. Yet another failed attempt is quantum logic: if you insist on treating quantum superpositions as representing some unknown classical position of a particle, you need propositions about those positions to violate the rules of logic themselves.

Hundreds of experiments probing quantum mechanics have been performed, all with the same results: committing to a classical ontology in terms of "waves" or "particles" costs you more than just accepting that quantum objects are different from either.

Physicists have spent a lot of energy thinking about this. All of the author's claims were under active debate in the 1920s. He is just completely ignoring the following century of investigation, and claiming that it never happened!

I actually don't like the double slit experiment because it's so easy to confuse yourself. Good for learning the math, maybe, but bad for presenting the "weirdness." Tests of Bell's inequalities are much more interesting and IMO cut straight to the heart of the weirdness of QM. Likewise with tests of the quantum Zeno effect. For me, at least, these two experiments go straight to "okay fine, measurement is weird and let's just treat superposition as its own thing" while double slit experiments beg for hand waving mysticism.

For me, at least, these two experiments go straight to "okay fine on https://www.lvbagsbe.com/replica-louis-vuitton-wallets.html

> Duane’s Law says that if a body is periodic in space in a given direction then momentum exchanges in that direction are quantized. That means that the emerging electron is more likely to go in certain directions than in others, depending on how many quanta of sideways momentum are exchanged. Guess what? When a stream of electrons is sent through, a ‘diffraction’ pattern results.

If this "direction preferentiality" were all that were needed to cause a diffraction pattern, then we should see it if we run the experiment with one slit closed for a while, and then the other slit closed for a while.

But that's not what happens! If you send particles through only one slit, you do not get a diffraction pattern! (Actually you do, but the valleys are spaced far wider than those with both slits open.) No diffraction pattern = no valleys. Running the experiment again with the other slit closed can't add those valleys in. This is logically no different than individual electrons simply "randomly" entering alternate slits, so that can't make a diffraction pattern either.

What am I missing? It seems like the author is trying to explain double-slit purely in terms of statistical ensembles of quantum-ish particles rather than exploiting the full generality of quantum fields, which makes no sense simply by looking at the results of a single- vs. double-slit setup. (e.g. https://en.wikipedia.org/wiki/Double-slit_experiment#/media/...)