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284
Account age
3 yrs
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🧰 Free analysis for Sjoerd Visscher
Known for
18 views
Isn't it amazing that these are all different representations of the same thing, each useful in its own way?
11 views
I believe proarrow equipments are a great setting to study optics in. You can see the expression for optics and the equivalent string diagram below.
The string diagram even looks like it's just a schematic drawing of an optic, but it really contains all the required information! The arrow heads indicate that s, t, a and b are all tight arrows, but in the loose direction.
If you specialize to the p
![(comult @(D '["Y"]) == line || counit)
|| (comult @(D '["X"]) == mappend @(D '["X"]))
|| (comult @(D '["Z"]) == counit @(D '["Z"]) || line)](/img?u=https%3A%2F%2Fpool.jortage.com%2Ftypespl%2Fmedia_attachments%2Ffiles%2F116%2F097%2F842%2F621%2F387%2F824%2Fsmall%2F9a8002e91dada78e.png)
8 views
(comult @(D '["Y"]) == line || counit)
|| (comult @(D '["X"]) == mappend @(D '["X"]))
|| (comult @(D '["Z"]) == counit @(D '["Z"]) || line)
5 views
line || unitAdj @"L" @"R" == counitAdj @"L" @"R" || line
📊 Post engagement
5
Avg engagement / post
1.8%
Engagement vs followers
Nov 2022
On Mastodon since
🔥 Top post: Isn't it amazing that these are all different representations of · 18 likes + reposts
📊 Activity & format
Posting cadence
0.23 / week
A lower-frequency account — each post lands with more weight.
Content mix
Mostly images
Recent: 5 text · 7 image · 0 video.
Follower / following
1.2×
Follows 233 back. A more reciprocal / networked account.
Recent posts
View on Mastodon ↗
🔥 Top post
Isn't it amazing that these are all different representations of the same thing, each useful in its own way?
I have an elasticube wooden puzzle at home, and yesterday I saw a version in a museumshop with balls instead of cubes. This allows for different shapes to be made, but the smooth surface of the balls caused the shapes to lack stiffness. So…
I've added the cospan category to the proarrow library. [1] I thought it wouldn't be possible to implement it, since the composition of cospans requires pushouts. And pushouts are an inherently dependently typed concept, since the pushout …
Ah I see it now, both sources talk about thinnings as being morphisms in the augmented simplex category. I read that as thinnings being the morphisms in the augmented simplex category, but it is meant as being a subset.
I keep reading that the augmented simplex category and the category of thinnings are the same thing, but I don't think that's true? The morphisms can both be seen as functions from Fin n to Fin m, but in the simplex category the constant f…
trace @_ @(D '["A"]) @(D '["X"]) @(D '["Y"]) (node "f" == node @'["Z"] "g")
line || unitAdj @"L" @"R" == counitAdj @"L" @"R" || line
(comult @(D '["Y"]) == line || counit)
|| (comult @(D '["X"]) == mappend @(D '["X"]))
|| (comult @(D '["Z"]) == counit @(D '["Z"]) || line)
Photo post
@mc Do you think dependent optics might fit in this framework?
You could even see the above string diagram as a comb. Chad Nester et al. figured this out for the free cornering in https://arxiv.org/pdf/2205.00842 but it works for any proarrow equipment!
I believe proarrow equipments are a great setting to study optics in. You can see the expression for optics and the equivalent string diagram below.
The string diagram even looks like it's just a schematic drawing of an optic, but it reall…
trace @_ @(D '["A"]) @(D '["X"]) @(D '["Y"]) (node "f" == node @'["Z"] "g")
line || unitAdj @"L" @"R" == counitAdj @"L" @"R" || line
(comult @(D '["Y"]) == line || counit)
|| (comult @(D '["X"]) == mappend @(D '["X"]))
|| (comult @(D '["Z"]) == counit @(D '["Z"]) || line)
Photo post
@mc Do you think dependent optics might fit in this framework?
You could even see the above string diagram as a comb. Chad Nester et al. figured this out for the free cornering in https://arxiv.org/pdf/2205.00842 but it works for any proarrow equipment!
I believe proarrow equipments are a great setting to study optics in. You can see the expression for optics and the equivalent string diagram below.
The string diagram even looks like it's just a schematic drawing of an optic, but it reall…
🐘 Community & instance
Home server
types.pl
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✅ Link-verified
Verified link
Proved ownership of a website linked on their profile — Mastodon's green-check verification, a real identity signal rather than a paid badge.
On Mastodon since
Nov 2022
Joined in the Twitter-exodus wave of late 2022 — part of the migration that made Mastodon a real destination.
💡 Facts
🗓️Joined Mastodon in 2022 — 3 years ago.
👁️Averages 5 views per post.
📤Posts about 0.2× per week.
🛡️ Audience credibility
89/100
Excellent
Credibility score
99%
Real
Real audience
Low
Fake-follower risk
High
Data confidence
- Est. 99% real, active audience · Low fake-follower risk.
- Strong engagement (~1.8% of followers engage each post) — an active, real audience.
- Verified account.
- Established account (3+ years old).
Heuristic estimate from engagement, follower ratios, account age & growth — a screening signal, not a guarantee.
About
he/him #haskell #categorytheory #lumatone
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EstimatedEstimated shared audience with similar creators — useful for avoiding overlap (or doubling down) when planning a campaign.
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