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Matteo Capucci

@mattecapu.bsky.social

505 followers 264 following 74 posts

🇮🇹, amateur professional poster and professional amateur mathematician (general abstract nonsensology applied to systems theory & cybernetics), aspiring psycohistorian. shitposting isn't endorsement. You can't find me here, I'm on @mc@mathstodon.xyz

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Matteo Capucci @mattecapu.bsky.social · 17/02/2025

normalize poems in math (from ncatlab.org/nlab/show/%C...)

Poem

There is an interesting stanza from a song of Léo Ferré:

Et que les globules figurent

Une mathématique bleue,

Sur cette mer jamais étale

D’où me remonte peu à peu

Cette mémoire des étoiles.

— (Léo Ferré, La mémoire et la mer)

He also mentions geometry and ‘théorème’ elsewhere in the song.

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Matteo Capucci @mattecapu.bsky.social · 14/02/2025

not on my bingo card: an ε-δ definition of continuity in category theory (from 'Homotopy Linear Algebra' arxiv.org/abs/1602.05082)

Let Lin ←−− be the ∞-category whose objects are the presheaf categories SS with S locally finite, and whose morphisms are the continuous linear functors: A linear functor F : ST → SS is called continuous when for all ε ⊂ S there exists δ ⊂ T and a factorisation ST // F Sδ Fδ SS // Sε. Here we quantify over finite groupoids ε and δ with full inclusions into S and T ; the horizontal maps are the projections of the canonical pro-structures.

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Matteo Capucci @mattecapu.bsky.social · 30/01/2025

*screams in efficient market hypothesis*

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Matteo Capucci @mattecapu.bsky.social · 30/01/2025

today's (well-known) trick in category theory: the pasting law for pullbacks works in two directions, i.e. if the right square below is a pb then the left square is a pb *if and only if* the pasting is in other words: drawing the pb corner on the right isn't ambiguous notation