diffgeom.bsky.social
Differential Geometry, an online shop at diffgeom.com
Run by Andrew D. Hwang ("Hwang" rhymes with "song" more or less), he/him: Freelance mathematician and mathematical artist (no machine learning), difficult to summarize
125 posts
318 followers
212 following
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Just FYI, I added your shop to diffgeom.org/misc/math_sh...
Please pass along other shops you may know about, and/or let me know if there are corrections to your entry!
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Tangentially, it looks to me that any proof must rely enough structure to determine angles in principle: Pythagorean theorem or equivalent. But a proof *can* be given using just the Pythagorean theorem by dropping a perpendicular and naming a couple of auxiliary sides. :)
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In Cartesian coordinates, put vertices at (0,0), (a,0), (b,c), (a+b,c).
Sum of squares of diagonals
= [(a+b)^2 + c^2] + [(a-b)^2 + c^2]
= 2(a^2 + b^2 + c^2)
= 2(sum of squares of sides).
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Probably not me then, FWIW; my spirals are all on tori. I've designed wearable loxodrome-banded spheres, but haven't offered them for sale....
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Please do email or DM details (or post them if you're willing)!
A lot depends on whether this is a mathematical or practical question, and how strictly "preserve" is meant.
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There *are* definite mathematical kinships with spirograph! :)
diffgeom.com/blogs/about-...
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Thank you for your kind comment! It's always a pleasure to see these for the first time again. :)
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But also well-deserved: Your image is striking (good) and inviting!
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Nervous System gifts for Math People!
1. Spectre Tile puzzle n-e-r-v-o-u-s.com/shop/product...
2. Infinite Galaxy Puzzle n-e-r-v-o-u-s.com/shop/search_...
3. Reaction Möbius jewelry n-e-r-v-o-u-s.com/shop/search_...
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For what it's worth (and to make a long story short), these pieces are now offered everywhere I ship, so the page should load for you. :)
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Just saw all your investigation results. Thank you for the thorough debugging (and apologies for effectively inducing you to)!
Early this morning it occurred: I'm only offering this piece in the US.... ::oops::
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If you know of similar shops that are "unlisted" please pass them along!
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(i) Thank you! and (ii) Hmmm. :S
The link worked for me just now. Are you still getting a 404...?
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And today is an assembly day. Beautiful brass #mathjewelry heading out to Gallery North on Long Island
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💞
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To clarify, there is no reason to believe more than this user deleted their bsky account. "Safety" here refers to "safe spaces." The concern is whether bsky (not MathSky) *is* a safe space, and if not, what can be done.