Oh Dear!
A nearly trivial demonstration that Quantum Mechanics is actually real and that reality isn’t… or isn’t like what we think is real.
Two crossed polarizers block all light. Add a 3rd at 45 decrees to both, it ought to help block. Instead, more light gets through. Easily demonstrated. In agreement with QM theory. Darned weird. Oh, and it basically says either the property of locality doesn’t exist (things can have effects at a distance) or the property of realism is wrong (that there is no underlying state that a particle must obey).
So where does that leave reality if there is no underlying force for reality, or if actions can happen at any distance?
How can this be used to create “impossible” machines?
If more photons can go through more filters could more protons go through more atomic shells to fuse in nuclei? Might it not just take MORE shielding electrons instead of less?
It’s clear that to really make this next leap of actual devices, one must understand what QM says really happens.
Musings from the Chiefio 
Is the third filter, the one at 45 degrees, between the light source and the filters or after the 2 filters at 90 degrees?
It is between the two filters at 90 degrees in most images, but maybe in front in others. I’ll need to watch it again to be sure. I think the order does not matter.
In the example you can see without running the video, the light is from the light box on the bottom of the stack, then 2 filters at 90 degrees are placed so you can see the dark intersection. Finally, the filter from the right is brought in between those 2 in the series from light box to eye and the dark wedge lightens.
In the video, they show inserting the 3rd filter between the two at 90 degrees (so light vert 45 horz eye) but I don’t remember if one of them was shown as an active example with it in front or behind, or if it was the “illustrations”. I’ll re-watch the video looking for that, but later in the day. You might want to just watch it now and post the result.
I’m fairly certain order does not matter, though in the first few minutes of the first example they reference adding filters between the two at 90 degrees to each other.
This demonstration plus various recent entanglement experiments do show how weird reality is in light of QM. The only “solution” that makes sense to me is there must be another unseen dimension that facilitates these phenomena. Or, more generally, that QM is not a complete description of reality.
If angles are quantized like time and space, then there could be a finite number of hidden variables, one for each filter combination, that determine if a given photon would pass through a given combination of filters.
@JP Miller:
For this example in particular, I could see a case where a filter might not be blocking 100% of photons out of alignment, but might be ‘twisting’ some into alignment. Then a stack of filters at 15 degrees rotation to the prior filter might be just ‘twisting’ the orientation of VERY out of alignment photons into alignment… where a full 90 degree ‘twist’ might be impossible in one go.
I’m sure someone will have thought of that and tested it, though. It’s too obvious a possible answer.
More likely, IMHO, is like you said: we’re missing an entire basket of reality and can’t understand how things work as it involves stuff we can’t sense or know.
Even if angles aren’t quantized, one could have an infinite number of hidden variable, one for each combination of filters. Some QM practitioners posit an infinite number of universes, so this idea shouldn’t be too much of a stretch for them :)
Just a peas and thimbles observation .. one that probably has no impact on the actual issue.
The discussion and Venn diagrams and examples are not always discussing the same “thing” in the way we customarily expect words to attach to things.
The polarized filters affect WAVES. But the numerical analysis / example counts PARTICLES. (The images and discussion is based not on a probability from zero to one hundred PERCENT , but on the behavior of individual particular photons circled up in a population of 100 identical individuals) Waves in, particles out.
Even 40 years ago the introductory texts I had inflicted on me, discussing this weirdness, introduced the notion of a WAVI-CLE, where one individual photon, (and assuming such a “thing” only provisionally) existed in the whole universal infinitely lengthed field of space-time, like a very very long and wiggly snake. And if you tapped the snake on the head, or in the middle, or at the tail, you would necessarily affect the behavior of the whole snake. And the “feeling” of the “tap” should not be considered to “move” along the infinite length of the wavical snake at a particular speed, especially not at a speed greater than light, because the whole snake and all of the wiggles in the snake existed in the same length of space, whether we consider that length zero or infinite or any distance in between.
Of course this was all introduced to me before string theory and branes. No doubt the introductory matter in contemporary High School textbooks offers other analogies.
Which introductory matter is all no doubt bogus. “Lies we tell children to engage their attention”. It’s why words and “realistic” analogies aren’t used in QM and maths of several sorts — including statistical probabilities — are used instead.
But thanks for the link to the video, it DID engage this ADULT’s attention and very nicely meets your defined mission of highlighting “mind pleasers”. Carry on.