Saturday, 2017 September 9, 20:01 — merch

a poster

Sometimes I search my blog for this picture and scratch my head in puzzlement that it’s not here, before remembering that I posted it on Google Plus back when I used that.

So here it is. Stephen Guerin, founder of, displays his canvas print of one of my designs.

The colors came out better than I hoped, in stark contrast to a couple of mugs with related designs that I got from the same shop.

Monday, 2017 July 3, 19:43 — eye-candy, mathematics, me!me!me!

mutant dragons

In 2007 I thought of a pretty way to paint a square so that all pixels are different, but similar colors are clustered. For each pixel, set x,y to its coordinates; if their sum is odd, set the low bit of one of the color channels to 1. Replace x,y with (-x+y)>>1, (-x-y)>>1; this has the effect of rotating the grid by 3/8 turn and shrinking it by a factor of √2, so that the former even points, which formed a larger oblique grid, now fall on the original grid, and the odd points have their new half-coordinates truncated away. Repeat until a bit has been assigned to each bit of the three color channels.

Colors that share their higher bits form twindragon fractals, thus:

In 2012, I thought: what if the rotation alternates clockwise and counterclockwise?

A bit on the boring side.

But in 2017, I thought: what if the sequence of left and right turns is randomized? ( . . more . . )

Tuesday, 2017 June 20, 23:06 — cartoons

And so it reiterates

In the last couple of years I’ve looked at thousands of webcomics. Sometimes I wish I’d kept a list of those whose first page is captioned “It begins” or “So it begins” or “And so it begins.”

Saturday, 2017 June 3, 21:28 — sciences

how (some) fireflies do it

Fireflies in Borneo have a wonderfully simple and distributed way of synchronizing their blinks.

If I had the skill I’d make a screensaver of it. A couple of ways to play with the concept:

I wouldn’t expect all bugs to have exactly the same period, but how much variation is tolerable? What if there are two populations, indistinguishable except that their periods differ irrationally?

What if each bug has a different hue, and responds only to others that are near on the color wheel (perhaps only in one direction)? Might a stable cycle result, rather than synchrony of all?

Saturday, 2017 May 27, 17:30 — heraldry, language, prose

less than fifty years later

I’ve read Heinlein’s Red Planet three times, starting at age seven or eight, and each time I soon forgot most of the plot. One thing that stuck with me was that the school’s new head signaled his evil by ordering the boys to paint their space-helmets a uniform brown, in place of tiger stripes and other fanciful personalizations; I think that helped trigger my early interest in heraldry!

Another random bit that stuck with me is the place-name Charax, which I took to be a crude approximation to the Martian name, said to be very hard for humans to pronounce with its “triple gutturals”. Today I learned that Charax was a Roman camp in Crimea.

Tuesday, 2017 May 23, 16:19 — cinema, language

questions of emphasis

In Sherlock episode “The Lying Detective”, the phrase serial killer is uttered many times, always stressing the first word – as if the second were a given, even when (for the speakers) any killings are hypothetical. That impaired my enjoyment of a generally well-written episode. (Well, much better-written than its neighbors.)

I’ve noticed the phenomenon before: when a phrase becomes a fixed lexeme, many people, perhaps most, are deaf to its components. For my ex, the phrase beef jerky was in such perfect union that she often said “turkey beef-jerky”. Not Always Right has occasional tales of restaurant workers and customers for whom the title “bacon lettuce & tomato sandwich” does not imply the presence of bacon.

Tuesday, 2017 April 11, 20:55 — blogdom

you can talk to me now

When I changed the site to HTTPS but didn’t change a corresponding setting in WordPress, comments were broken. Should be working now.

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