The Action Lab - Ulexite (How Does Television Stone Work?)

A piece of Ulexite is like a bunch of fiber-optic cores made into a grid and it has different refractive indices in different directions of polarization. See also Iceland spar or optical calcite which is a planar version of Ulexite and is birefringent and also piezo-electric. Many people can percieve effects of polarization entopically. See Haidinger's brush which may be a phenomenon related to that which Vincent van Gogh saw in the shimmering halo around lights which he depicted in The Night Café.

1:04 I can't figure out what he's doing with his phone screen there. Maybe he has a bit of polaroid in front of the camera? But that doesn't explain the pattern that it leaves behind. That's weird!

The wave optics simulator is at https://phydemo.app/ray-optics/simulator/. It's quite good fun. It only 2D so it doesn't do these crystals though, just mirrors and a 'beam splitter' which would be something like a Nicol prism. A more advanced tool would allow you to build electrical circuits and model the electric field effects on the crystals. See David Dorran - The z-Transform and David Hestenes - Tutorial on Geometric Calculus. These things aren't necessarily difficult to simulate: see Geometric Algebra. For more lab stuff, see Ben Krasnow Identifying Chemicals by Nuclear Quadrupole Resonance.

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Maybe one day we will be able to describe what it means to measure time!

How an Atomic Clock Really Works, Round 2: Zeeman Alignment

12:43 on the tuning of the clock using a C-field. This involves shielding the tube from the earth's magnetic field and adding back a well-controlled field, then compensating for that well-controlled field's effects as part of the calibration process. The reason for the non-zero C-field is to establish a polarisation orientation for the caesium atoms (see Feynman on polarization below). The effect is to move the transition lines apart to make the quantum selection rules intelligible. (It's a bit like Norman Wildberger's Parity Staff  Notation for music. It's so that the left hand doesn't need to worry about what the right hand is doing!) The even more amazing bit is that they use dependence of the Zeeman splitting on the field strength to calibrate the C-field. So it's a process of dynamically settling on a fixpoint similar to biological homeostasis. 25:18 the process in practice involves knowing exactly what a mixer is, it seems. HP didn't really explain that in the documentation.

Here's part 1: 

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Ben Krasnow on how difficult it is to separate the magentic and electrical effects of large blocks of metal such as you have in a Stern-Gerlach apparatus. A couple of blocks of cold steel have a similar Zeeman-type effect to a 0.8 Tesla magnetic field between two neodymium magnets.

Effect of magnetic fields on flames:

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See Ice and the tensor videos in I'm Drowning in My Own Sh*t Here; and also Feynman's book QED: The Strange Theory of Light and Matter, on page thirteen of the paperback Penguin edition I have:

We begin with light. When Newton started looking at light, the first thing he found was that white light is a mixture of colors. He separated white light with a prism into various colors, but when he put light of one color -- red, for instance -- through another prism, he found it could not be separated further. So Newton found that white light is a mixture of diifferent colors, each of which is pure in the sense that it can't be separated further.

(In fact, a particular color of light can be split one more time in a different way, according to its so-called "polarization." This aspect of light is not vital to understanding the character of quantum electrodynamics, so for the sake of simplicity I will leave it out -- at the expense of not giving you an absolutely complete description of the theory. This slight simplification will not remove, in any way, any real understanding of what I will be talking about. Still, I must be careful to mention all of the things I leave out.)

Then, on Page 149:

I would like to emphasize something. The theories about the rest of physics are very similar to the theory of quantum electrodynamics: they all involve the interaction of spin 1/2 objects (like electrons and quarks) and spin 1 objects (like photons, gluons, or W's) within a framework of amplitudes by which the probability of an event is the square of the length of an arrow. Why are all the theories of physics so similar in their structure?

There are a number of possibilities. The first is the limited imagination of physicists: when we see a new phenomenon we try to fit it into the framework we already have -- until we make enough experiments, we don't know that it doesn't work. So when some fool physicist gives a lecture at UCLA in 1993 and says, "This is the way it works, and look how wonderfully similar the theories are," it's not because nature is really similar; it's because the physicists have only been able to think of the same damn thing over and over again.

Another possibilty is that it is the same damn thing over and over again -- that Nature has only one way of doing things, and She repeats her story from time to time.

A third pocssibility is that things look similar because they are aspects of the same thing--some larger picture underneath, from which things can be broken into parts that look different, like fingers on the same hand. Many physicists are working hard to put together a grand picture that unifies everything into one super-duper model. It's a delightful game, but at the present time none of the speculators agree with any of the other speculators as to what the grand picture is.

See Feynman diagram on Wikipedia.

I think the grand picture is the mystical whole, which our language divides into parts as we develop our different descriptions of it. The coherence of the parts is according to coherence of the languages we use to describe them. See Numberphile - Sophie Maclean on the Catalan Numbers.