Uploaded July 2024 | Updated September 2026, 2 weeks ago
Title: Communicating Relational Thinking
Abstract: In this talk I will give an overview of our recently completed experiment of communicating categorical thinking to a STEM-oriented audience outside mathematics. Angeline, Brendan, Paul and myself recently authored a free online textbook titled "Relational thinking: from Abstractions to Applications". In this talk, I will walk through the contents of the book and equally importantly the open source technologies behind the book. This talk is an invitation to the audience not only to read the book but also to create their own inclusive material around category theory / math leveraging new technologies.
https://topos.site/events/berkeley-seminar/
Title: Communicating Relational Thinking
Abstract: In this talk I will give an overview of our recently completed experiment of communicating categorical thinking to a STEM-oriented audience outside mathematics. Angeline, Brendan, Paul and myself recently authored a free online textbook titled "Relational thinking: from Abstractions to Applications". In this talk, I will walk through the contents of the book and equally importantly the open source technologies behind the book. This talk is an invitation to the audience not only to read the book but also to create their own inclusive material around category theory / math leveraging new technologies.
https://topos.site/events/berkeley-seminar/
![[Berkeley Seminar] Kevin Carlson (Topos Institute) | Exponentiability
Title: Exponentiability
Abstract: I’ll report on Ea Thompson and my recent preprint, discussing how to classify cocontinuous functors on categories of models of a sketch, with immediate applications to exponentiability in general, and how we reduce the general result to manageable conditions in the case of exponentiable virtual double categories.
Date: June 16, 2026 [Berkeley Seminar] Kevin Carlson (Topos Institute) | Exponentiability](https://i.ytimg.com/vi/9Kr-Oigw9bg/mqdefault.jpg)

![[DOTS Lectures] 12. A general representability theorem for Systems Theory Pt. 2
Part of a lecture series on the Double Operadic Theory of Systems (DOTS) presented by David Jaz Myers.
Some material from these lectures can be found in Davids book on categorical systems theory:
https://www.davidjaz.com/Papers/DynamicalBook.pdf [DOTS Lectures] 12. A general representability theorem for Systems Theory Pt. 2](https://i.ytimg.com/vi/A4GaF2eAodY/mqdefault.jpg)
![[Berkeley Seminar] Harrison Grodin | Amortized Analysis via Coalgebra
Title: Amortized Analysis via Coalgebra
Abstract: Amortized analysis is a technique for analyzing the efficiency of operations on a data structure in which cost is studied in aggregate: rather than considering the cost of a single operation in isolation, one bounds the total cost encountered throughout multiple operations in sequence. Traditionally, amortized analysis is phrased inductively, quantifying over finite sequences of operations. Connecting to prior work on coalgebraic semantics for data structures, we develop the alternative perspective that amortized analysis is naturally viewed coalgebraically in a category of cost algebras. In addition to simplifying the precise definition of amortized analysis, this perspective also generalizes the technique to other settings and incorporates type- and category-theoretic intuition.
https://topos.institute/events/berkeley-seminar/ [Berkeley Seminar] Harrison Grodin | Amortized Analysis via Coalgebra](https://i.ytimg.com/vi/A4TTyeVsheM/mqdefault.jpg)



![[Oxford Seminar] Matteo Capucci | A Second Taste of Quantitative Logic
Oxford Seminar, December 4 2025
Speaker: Matteo Capucci
Full Title: A Second Taste of Quantitative Logic
Abstract: In this second talk I will introduce p-means and argue they form a good quantitative analogue of first-order quantifiers. I will then sketch the construction of a hyperdoctrine valued in enriched graded preorders which forms the intended semantics of a first-order quantitative linear logic. [Oxford Seminar] Matteo Capucci | A Second Taste of Quantitative Logic](https://i.ytimg.com/vi/BAwK-X-8pIw/mqdefault.jpg)
![[DOTS Lectures] 13. A general representability theorem for Systems Theory Pt. 3
Part of a lecture series on the Double Operadic Theory of Systems (DOTS) presented by David Jaz Myers.
Some material from these lectures can be found in Davids book on categorical systems theory:
https://www.davidjaz.com/Papers/DynamicalBook.pdf [DOTS Lectures] 13. A general representability theorem for Systems Theory Pt. 3](https://i.ytimg.com/vi/BST8hBWS1Kw/mqdefault.jpg)
![[2-torial] Quantum information theory, Part 3: Quantum bird watching
2-torial, May 20 2026
You can find accompanying notes and other information on this video at https://topos.institute/work/lectures/2-torials/2026-05-20_hosgood_quantum/
Tutor: Tim Hosgood
Tutee: Jason Brown
The elements of quantum information theory are not so complicated: some linear algebra over the complex numbers and a bit of classical probability theory. But it doesnt take long before you run into some intriguing problems that showcase how established experimental results contradict our classical intuition. In this 2-torial we will learn the very basics of quantum theory, see how a Mach–Zehnder interferometer gives a real-world implementation of a classically impossible construction and suggests that we should go all in on complex numbers, and finally how this all applies to the world of theoretical bird watching via the Quantum Zeno effect. [2-torial] Quantum information theory, Part 3: Quantum bird watching](https://i.ytimg.com/vi/BfX-vy47fZw/mqdefault.jpg)
![Adrian Miranda: Kleisli constructions for pseudomonads
Topos Institute Colloquium, 30th of January 2025.
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The passage from a monad (A,S) to its category of algebras (resp. category of free algebras) can be seen as a V = Cat weighted limit (resp. colimit) construction [1]. The colimit case also has a description involving maps of the form X to SY and the so-called Kleisli composition.
When we move to the two-dimensional setting, the 2-category of pseudoalgebras can be seen as a V= Gray enriched weighted limit [2], but neither of the familiar descriptions of the Kleisli category categorify to give a weighted colimit [3]. We give a third, less well-known description of the Kleisli category which does categorify to the pseudomonad setting to give a weighted colimit. We show that comparisons induced by pseudoadjunctions splitting the pseudomonad are biequivalences if and only if their left pseudoadjoints are biessentially surjective on objects. This allows the more familiar Kleisli constructions for pseudomonads to be seen as tricategorical colimits, and for the development of the formal theory of pseudomonads pt. 2. Adrian Miranda: Kleisli constructions for pseudomonads](https://i.ytimg.com/vi/BksyGqtwjyg/mqdefault.jpg)