Jos Dingjan

Physicist, sailor, reader, organiser, geek.
L-Space is my spiritual home.
He/him or they/them.

:flag_pride:: Ally
AI: Fuck off

Last Notes

2026-07-20 07:22:25 UTC

Searching for “bull hitch” on Wikipedia. No hits[1], but the Search Results page previews a Wikiquote from the Sedenion entry, by @npub1nf4…nqe4 [2][3]
😄
Small world etc.
[1] (fine, I’ll dig out my copy of Ashley’s… nope. Knotspedia then. Ah yes.)
[2] ‘In January 1844, Graves sent three letters to Hamilton expanding on his discovery. He considered the idea of a general theory of “2^m-ions”, and tried to construct a 16-dimensional noemde division algebra, but he “met with an unexpected hitch” and came to doubt this was possible.’
[3] “hitch” in the quote, “bull” because the quote is from the Bull. Amer. Math. Soc.

2026-06-20 11:17:34 UTC

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The Voorlinden museum in Wassenaar has a Skyspace by Turrell, very impressive. It’s listed in James Turrell’s Dutch Wikipedia entry (and vice versa in the Museum Voorlinden entry), but not the English one (or under skyspaces).

2026-03-24 14:38:38 UTC

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With that and my experience doing tech. consulting (more or less R&D-department-for-hire/mad-inventors-for-hire) I feel that your €1300/day is more than reasonable for the expertise you’d bring, but I don’t know whether they’d be willing to pay that. They should, but should doesn’t put food on the table. Don’t let ‘em make you feel like you’re overasking, ‘s what I’m saying.

2026-03-24 12:44:12 UTC

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How many effective hours would you expect to be able to make in such a day? And/or what is your ratio of doing paid work versus being in between paid work?
When I worked as a technology consultant my rate (which went into the project costings in terms of hours-of-effort-to-achieve-$result to get to a per-project cost for customers) was about 280-300 €/h, with more senior technology consultants 40%+ more than that. I was expected to do at least 60% direct work, ideally 80%+, but we also had a fair number of ppl who were indirectly funded (business developers, mgmt, finance dep’t, IT support, etc). And this was over a decade ago, so let’s not forget inflation.
For skilled specialised work I think your €1300/day is a bargain. People need to value expertise.
(I have no idea about business consultancy)

2026-03-13 15:08:00 UTC

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Why?!?
Why, when you post about energy & climate & sustainability, would you use genAI slop that offers no actual benefit, just statistical word-correlation and answer-shaped objects, at tremendous cost in energy & water, actual capability of thought, immorally trained on stolen material, rife with biases, and only to disempower the majority and vastly enrich the 0.1%?

2025-10-05 09:48:50 UTC

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I don’t think they update those predictions for current events at all, I’ve always taken them to be longer-term stats (“travel climate” rather than “travel weather”)

2025-07-19 19:56:45 UTC

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So, doing a Stone-Wales-transform on a triangular prism transforms it into a triangular prism.
https://fsn1.your-objectstorage.com/drum/media_attachments/files/114/881/656/442/590/037/original/1aac4c6c81587cc7.jpeg

2025-07-19 10:11:43 UTC

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Idly thinking about this: if we do not let polygons go below triangles the number of faces is conserved, so the sum over N_i for i = 3…i_max is constant (with N_i the number of polygonal faces with i sides, with i_max… I’d have to sit down with paper to figure it out for a bucky ball, essentially the max-sided polygon if you reduce all other faces to triangles). That’s one constraint on the # of different shapes you can construct.

2025-07-18 11:27:25 UTC

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That article doesn’t make any skim-reading sense. “Depending on the length and width of the filaments, each whisker can have a direct current (DC) resistance of 10 to 40 watts.” WTF? Currents in mA³ WTF?

2025-05-15 20:58:53 UTC

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WHOAH!
The European Citizens’ Initiative calling for a ban on conversion practices in the EU has reached the “7 countries pass the threshold”-condition, and gained 250k supports in the last couple of days, so… the missing 250k to get to 1M total supports by the 17th might just be doable.
EDIT: 170k to go as of this morning, 100k to go at lunchtime. We’re doing it!
Let’s give this a massive final push and get there!
https://eci.ec.europa.eu/043/public/#/screen/home
#LGBTQ+ #LGBTQ #LGBTQIA #EU #BeingDecentHumanBeings

2025-05-13 21:12:26 UTC

Happy to say that the #Netherlands reached the threshold late last night, and #Slovenia followed tonight!
Sadly the overall petition is not likely to make it (more than half a million shy with less than four days to go) 😔 but any additional country strengthens the statement.
After Slovenia: #Germany, #Sweden and #Denmark are the next-closest.
https://eci.ec.europa.eu/043/public/#/screen/home
#LGBTQ+ #LGBTQ #LGBTQIA #EU #BeingDecentHumanBeings
https://mendeddrum.org/@happydisciple/113990973230121000