You won’t believe what this space is homeomorphic to

A serendipitous encounter with an intriguing exercise led me to an Eureka! moment, with great beauty involved.


The one integration secret mathematicians don’t want you to know

Hey folks, it's been a while! One of my New Year's resolutions is to write more on this blog (at least weekly, says the list), so here I am. My biggest impairment in doing so has been the feeling of incompetence about a lot of the stuff that interests me, hence my good intentions crashed … Continue reading The one integration secret mathematicians don’t want you to know

On humanities papers and mathematical naivety.

I just finished reading What does a mathematical proof prove?, a (supposedly) classic in philosophy of math by Imre Lakatos and it confirmed what I feared was happening: I can no longer bear any humanities paper. Everything[0] you read typically has a 10x multiplier on words, and usually boils down to one/two interesting perspectives on … Continue reading On humanities papers and mathematical naivety.

Perspectives on categories.

Category theory is a very fascinating area of mathematics. It's unexpectedly powerful in an incredible width of different contexts, from the purest abstractions to the most concrete applications. I'm far from being an expert in category theory, although I enjoy fiddling with it and looking through the categorical lens at the material of my courses. … Continue reading Perspectives on categories.

A game with AC, plus the story of a poster.

Today I stumbled upon an interesting article about a 'paradoxical' appearance of the axiom of choice in a generalization of the known 'hats on prisoners' puzzle. Two Three interesting thing in the linked page: The generalization of the game: multiple colours, infinite prisoners. I also guess ultrafilters appear, in disguise, when talking equivalences on infinite … Continue reading A game with AC, plus the story of a poster.


La playlist di questo mese è uscita proprio bene, perciò merita una menzione speciale. Si tratta di una playlist breve, che non raggiunge l'ora (58 minuti), e questo sicuramente contribuisce a darle coerenza. In linea con il trend degli ultimi mesi, la percentuale di canzoni italiani è ampissima (12/17), con un'importante ma attesa presenza di … Continue reading march18