A music theory analysis of SUNN O)))

I’ve complained before about music theory, and how it fails to actually address any of the music I actually like. One kind of music I have in mind is drone music. Consider, for instance, this reddit thread on the music theory of SUNN O)))

Honestly most drone is fifths and minor scales, it’s not really complicated.

The attitude being expressed is that drone music is too simple to require any music theory. This is a failure to engage with the music on its own terms. If that’s all there is, then what, pray tell, distinguishes different songs and artists? Are they just all interchangeable?

While it may be the case that drone music is particularly simple, I feel that this only makes the lack of a music theory all the more frustrating. Most music theory is frankly too complicated for me to understand, and it would actually be nice to have some simple music theory for once, if only music theorists didn’t think it was beneath them. In any case, I think the theory behind drone music is likely more complicated than they are making it out to be. Drone is highly preoccupied with texture (aka timbre)–a subject so difficult that music theory as a field has basically given up on it.

Anyway, in the spirit of being the change I want to see, I analyzed the spectrograms of a couple SUNN O))) songs.

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Moiré patterns with alternate shapes

A Moiré pattern is the interference pattern that emerges when you superimpose two grids that nearly line up. For instance, you could have two identical metal sheets with circular holes. If you put one in front of the other, and slightly rotate it, then you get a Moiré pattern.

Circular moire

Left: a Moiré pattern formed by two hexagonal grids of circular holes, one rotated by 5 degrees. Right: an artist’s (my) conception of the resulting Moiré pattern. This and all other images were drawn “by hand” (with Illustrator), so please accept some imperfection.

A reader expressed curiosity about what would happen if you replaced the circles with a different shape. As it happens, I am a former condensed matter physicist, which makes me a sort of expert in lattices. So I already know the answer, but let me walk you through with illustrations.

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Basic epidemic math

We are living in an epidemic of armchair epidemiology, and far be it for me to contribute by giving my own feverish take as an expert of an unrelated field. Therefore, I solemnly swear that I will make no predictions about the present pandemic. I am not paid enough to make such predictions–and if you did pay me I would consider it my professional duty to find you a better expert.

What I can do for free, is read up on basic epidemiology, and digest the maths for you, dear reader. My sources: Wikipedia’s article on mathematical modeling and compartmental models, and some lecture notes I found. My expertise: during my PhD in physics, I frequently worked models like the one I’m about to discuss, only with electrons instead of people.

The SIR Model

The very first epidemiological that one learns about, is the so-called SIR model. This model divides the population into three groups (“compartments”): susceptible (S), infected (I), and recovered (R). Susceptible people are those who could be infected; infected people are those who are currently infectious; recovered people are those who are no longer infectious, and are immune to infection. “Recovered” can be a bit euphemistic, since one method of “recovery” is dying. Another method of “recovery” is by developing symptoms strong enough that the victim knows to quarantine themself (becoming less infectious).

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Factorial experiments

cn: It’s math

When I was an experimental physicist, one of the difficulties was the sheer number of different knobs you could tune… the power of the laser, the rate of laser pulses, the angle of the laser, the material being measured, the temperature, and numerous other knobs more difficult to explain. The search space was too large, and I had to judiciously choose what things to measure.

But in some ways, it’s easier in physics. I had a lot of physics theory to inform my expectations. Suppose you’re designing a website for a personal business, there isn’t quite as much theory to tell you what design features will drive business. You might be stuck trying everything, throwing stuff at a wall until something sticks.

It turns out there’s some interesting math behind this. If you throw everything at a wall, that’s an awful lot of things. But there are ways to throw fewer things at the wall and get about the same information from your experiment.

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Fractals from Newton’s Method

This is a repost of an article I wrote in 2008, over ten years ago!  This is the one that explains where my avatar comes from.

Today, I will explain how I created this:

Three-colored fractal

This is a fractal. A fractal is a pattern that contains smaller versions of itself. But it’s not just any fractal. It’s a fractal I created from something called Newton’s method.

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Intrinsic value of choice

I know that this question has practical and political implications, but for now, I’m treating it as a “just for fun” philosophical question.  Just wanted to be upfront.

What is the value of freedom of choice?  Does it have intrinsic value, or is its value purely instrumental?

A thing has “intrinsic value” if it is valuable in itself.  It has “instrumental value” if it is valuable because it is a means to get something else of value.  For instance, suppose we have a choice between mushroom and cheese pizza.  This choice has instrumental value, because it’s a means for people to have the kind of pizza they most prefer.  But does the choice also have intrinsic value?

Under an initial analysis, I thought the answer was “no”.  If I’m presented with a one-time choice between A and B, and I choose A, did the other option B do any good?  At least within a consequentialist ethical framework, it sure doesn’t seem like it.  After all, option B had no bearing on the consequences.

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