julesh @julesh.mathstodon.xyz.ap.brid.gy · 23hMy understanding of the new law in the uk is that it remains legal to marry your first cousin, but if you ever made a sex tape together, even for your own private enjoyment, you would get 5 years 100 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 16/10/2026@at Oh huh, makes me wonder how to write weird things like continuation and selection monads as infinitary lawvere theories, that isn't obvious how to do it 000 0
julesh @julesh.mathstodon.xyz.ap.brid.gy · 16/10/2026I intuitively feel like polynomial monads should be equivalent to infinitary Lawvere theories, ie. intermediate between finitary monads (which correspond to ordinary Lawvere theories) and general monads. But the nLab pages don't mention any such thing. Am I right or am I confused? 100 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 15/10/2026I'm on a train that stops in Ware, which in the hands of a couple of people with the timing to do the Who's On First routine might be the actual winner of funniest place name in English 000 0
julesh @julesh.mathstodon.xyz.ap.brid.gy · 13/10/2026I just saw a diplomatic convoy from St Lucia in Dalston in London, for sure they were visiting the amazing St Lucian bakery at Dalston Junction 000 0
julesh @julesh.mathstodon.xyz.ap.brid.gy · 11/10/2026"Is Material Girl a Marxist song", the greatest thread in the history of forums, locked by a moderator after etc etc etc 000 0
julesh @julesh.mathstodon.xyz.ap.brid.gy · 08/10/2026Like many people I am very worried for the near future of my field. I'm not a problem solver and I think the problem solving half of the field is toxic and they are deserving of literally everything that has happened to them. But the dialectic between problem solving and theory building has […]mathstodon.xyzOriginal post on mathstodon.xyz 010 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 06/10/2026@dimpase Something like 25 years ago I knew a similar chord on windows ME (?) specifically to type the é in Pokémon 000 0
julesh @julesh.mathstodon.xyz.ap.brid.gy · 06/10/2026Here is an extremely neat definition of dependent lenses I've never seen before, as kleisli morphisms of the extension (ie. the equivalence of categories from containers to polynomial functors) considered as some exotic kind of generalised monad 010 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 06/10/2026> apt install texlive-full *goes away to do some other stuff for a while* 000 0
julesh @julesh.mathstodon.xyz.ap.brid.gy · 05/10/2026New profile picture who dis (not sure I'll keep it yet) 000 0
julesh @julesh.mathstodon.xyz.ap.brid.gy · 05/10/2026It occurs to me that if actually working AI was developed 70 years earlier, as many of the earliest pioneers of the field apparently expected, it would definitely have been immediately taken over by hyper-capitalism back then too 000 0
julesh @julesh.mathstodon.xyz.ap.brid.gy · 05/10/2026When your brain is smooth so all the thoughts just run off it, that's called a thoughterfall 020 2
julesh @julesh.mathstodon.xyz.ap.brid.gy · 04/10/2026Reason number whatever that I already hate linux + kde coming from a mac: keyboard shortcuts for diacritics are just shit. After a ridiculous amount of trial an error I have managed to type ëẽéêèẹȩ, but as far as I can tell it is straight up impossible to type ė (a diacritic used in Lithuanian) […]mathstodon.xyzOriginal post on mathstodon.xyz 100 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 02/10/2026Just stopped in Morpeth, notably the only UK station that is named after a Dark Lord 100 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 02/10/2026Very proud that I successfully did my nails on a moving train without any major mishaps 000 0
julesh @julesh.mathstodon.xyz.ap.brid.gy · 01/10/2026Going to the AI shop, anyone need anything? 020 2
julesh @julesh.mathstodon.xyz.ap.brid.gy · 01/10/2026Doing machine learning (parametric anamorphisms) 010 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 01/10/2026RE: wandering.shop/@xgranade/1173609604… Several of these are historical and/or scams, but it's a constant source of confusion that the term AI now refers to at least 3 very different technologies that Actually Work: - LLMs and similar generative models - deep reinforcement […]mathstodon.xyzOriginal post on mathstodon.xyz 000 0
julesh @julesh.mathstodon.xyz.ap.brid.gy · 30/09/2026I noticed a small sign on a platform in Glasgow central station saying cctv footage is used to train AI models I guess you can opt out of it by walking to London 024 4
julesh @julesh.mathstodon.xyz.ap.brid.gy · 28/09/2026Rug discovery (visiting small carpet shops in cities like Tehran looking for undocumented designs) 010 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 24/09/2026In the very early days of applied category theory around 2018, I twote something to the effect that the next layer up from applied category theory will be design patterns In the last several weeks at Glaive I feel like we have finally reached the design patterns layer 010 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 24/09/2026@eigil Here's a fun thing: the version I wrote there was the simply type case, it is easy to construct essentially the same monad on the category of containers and dependent lenses, but to get the corresponding adjunction you need to make dependent adaptors 100 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 24/09/2026Here is the extremely tl;dr version of what's happening. The embedding of Set x Setᵒᵖ into lenses admits a left adjoint, and kleisli categories of the induced monad on lenses basically capture the essence of what open games are. And the crazy thing is that I totally knew about this adjunction in […]mathstodon.xyzOriginal post on mathstodon.xyz 110 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 24/09/2026Open games are evolving! Preview of a blog post I'm about to write 110 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 24/09/2026Train internet creating a very 21st century Cthulhu cult chant 000 0
julesh @julesh.mathstodon.xyz.ap.brid.gy · 23/09/2026Flashback to the one blog post I wrote so far about dependent optics: julesh.com/posts/2025-10-16-depende… I really need to continue this series. Unlike most blog posts I write this is not something I can do easily, this stuff is really complicated and I am a bit out of […]mathstodon.xyzOriginal post on mathstodon.xyz 020 2
julesh @julesh.mathstodon.xyz.ap.brid.gy · 20/09/2026We had a very close encounter with a very inquisitive fops 120 2
Reposted by juleshtheHigherGeometer @highergeometer.mathstodon.xyz.ap.brid.gy · 20/09/2026@julesh Gödel was reviewer 2 on Hilbert's program, supplying a counterexample to the main claim 011 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 20/09/2026Last week I went to 2 different events. Most of the time I was surrounded by mostly pure mathematicians at an event about AI, and on the whole everybody seemed to be extremely depressed and/or shellshocked about recent events. Then one evening I went to the new London Haskell meetup and it was […]mathstodon.xyzOriginal post on mathstodon.xyz 050 5
julesh @julesh.mathstodon.xyz.ap.brid.gy · 20/09/2026Hilbert was reviewer 2 to Euclid, finding all the mistakes 2500 years later 111 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 19/09/2026> "The agent escaped its sandbox" > looks inside > It's just evaling untrusted code again 020 2
Reposted by juleshtheHigherGeometer @highergeometer.mathstodon.xyz.ap.brid.gy · 19/09/2026Here's a question that occurred to me: suppose I have a symmetric monoidal category with diagonals and *one* projection (say \\(\mathrm{pr}_1 \colon A \otimes B \to A\\) (so diagonals and this projection is natural. is the monoidal structure necessarily cartesian? 132 3
julesh @julesh.mathstodon.xyz.ap.brid.gy · 19/09/2026RE: mathstodon.xyz/@mc/1172975366592084… It's lenses againmathstodon.xyz 020 2
julesh @julesh.mathstodon.xyz.ap.brid.gy · 18/09/2026It's not a magic box, it's a sufficiently advanced technology box 020 2
julesh @julesh.mathstodon.xyz.ap.brid.gy · 18/09/2026Bro, just ask Claude whether the Turing machine halts or not 021 2
julesh @julesh.mathstodon.xyz.ap.brid.gy · 18/09/2026One of the spots in London that can pass for Amsterdam 020 2
Reposted by juleshraganwald.com @raganwald.functional.cafe.ap.brid.gy · 16/09/2026“Selection functions and lenses,” from @julesh julesh.com/posts/2021-03-30-selecti…julesh.comJules Hedges - Selection functions and lenses 001 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 16/09/2026Flashback to this very short blog post I wrote 5 years ago: Selection functions and lenses julesh.com/posts/2021-03-30-selecti…julesh.comJules Hedges - Selection functions and lenses 010 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 16/09/2026Part 5 in the increasingly inaccurately named European Trilogy 010 1
julesh @julesh.mathstodon.xyz.ap.brid.gy · 14/09/2026One simple practical way to fight against corporations and some of the other bad people is to randomly interleave sexual content with serious work. For slightly complicated historical reasons most of them are puritan (the same ones we expelled from Europe back in the day) so I suspect it sort of […]mathstodon.xyzOriginal post on mathstodon.xyz 110 1