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In the first part, we have constructed several families of interacting wedge-local nets of von Neumann algebras. In particular, there has been discovered a family of models based on the endomorphisms of the U(1)-current algebra of…

Mathematical Physics · Physics 2017-09-26 Marcel Bischoff , Yoh Tanimoto

This is the fourth in a series of papers extending Martin-L\"of's meaning explanation of dependent type theory to higher-dimensional types. In this installment, we show how to define cubical type systems supporting a general schema of…

Logic in Computer Science · Computer Science 2018-07-20 Evan Cavallo , Robert Harper

It is known that one can construct non-parametric functions by assuming classical axioms. Our work is a converse to that: we prove classical axioms in dependent type theory assuming specific instances of non-parametricity. We also address…

Logic in Computer Science · Computer Science 2017-06-28 Auke Bart Booij , Martín Hötzel Escardó , Peter LeFanu Lumsdaine , Michael Shulman

To ensure decidability and consistency of its type theory, a proof assistant should only accept terminating recursive functions and productive corecursive functions. Most proof assistants enforce this through syntactic conditions, which can…

Logic in Computer Science · Computer Science 2026-05-01 Bastiaan Laarakker , Daniël Otten , Benno van den Berg

We develop algebraic models of simple type theories, laying out a framework that extends universal algebra to incorporate both algebraic sorting and variable binding. Examples of simple type theories include the unityped and simply-typed…

Logic in Computer Science · Computer Science 2020-07-01 Nathanael Arkor , Marcelo Fiore

We present new induction principles for the syntax of dependent type theories, which we call relative induction principles. The result of the induction principle relative to a functor F into the syntax is stable over the codomain of F. We…

Logic in Computer Science · Computer Science 2021-07-20 Rafaël Bocquet , Ambrus Kaposi , Christian Sattler

We contribute XTT, a cubical reconstruction of Observational Type Theory which extends Martin-L\"of's intensional type theory with a dependent equality type that enjoys function extensionality and a judgmental version of the unicity of…

Logic in Computer Science · Computer Science 2021-04-20 Jonathan Sterling , Carlo Angiuli , Daniel Gratzer

In the context of dependent type theory, we show that coinductive predicates have an equivalent topological counterpart in terms of coinductively generated positivity relations, introduced by G. Sambin to represent closed subsets in…

Logic · Mathematics 2024-04-05 Pietro Sabelli

In this article we study the K-theory of endomorphisms using noncommutative motives. We start by extending the K-theory of endomorphisms functor from ordinary rings to (stable) infinity categories. We then prove that this extended functor…

Algebraic Topology · Mathematics 2013-02-07 Andrew J. Blumberg , David Gepner , Goncalo Tabuada

Usual math sets have special types: countable, compact, open, occasionally Borel, rarely projective, etc. Each such set is described by a single Set Theory formula with parameters unrelated to other formulas. Exotic expressions involving…

Logic in Computer Science · Computer Science 2026-04-01 Leonid A. Levin

First-order logic with dependent sorts, such as Makkai's first-order logic with dependent sorts (FOLDS), or Aczel's and Belo's dependently typed (intuitionistic) first-order logic (DFOL), may be regarded as logic enriched dependent type…

Logic · Mathematics 2019-10-10 Erik Palmgren

This work proposes a dependent type theory that combines functions and session-typed processes (with value dependencies) through a contextual monad, internalising typed processes in a dependently-typed lambda-calculus. The proposed…

Programming Languages · Computer Science 2018-01-25 Bernardo Toninho , Nobuko Yoshida

We give a natural-deduction-style type theory for symmetric monoidal categories whose judgmental structure directly represents morphisms with tensor products in their codomain as well as their domain. The syntax is inspired by Sweedler…

Category Theory · Mathematics 2021-07-13 Michael Shulman

We study varieties generated by semi-primal lattice-expansions by means of category theory. We provide a new proof of the Keimel-Werner topological duality for such varieties and, using similar methods, establish its discrete version. We…

Logic · Mathematics 2023-08-29 Alexander Kurz , Wolfgang Poiger , Bruno Teheux

We extend the model structure on the category $\mathbf{Cat}(\mathcal{E})$ of internal categories studied by Everaert, Kieboom and Van der Linden to an algebraic model structure. Moreover, we show that it restricts to the category of…

Category Theory · Mathematics 2025-06-03 Calum Hughes

The category of contexts underlying a model of Martin-L\"of type theory with Unit-, $\Sigma$-, and $\Pi$-types need not be locally Cartesian closed, but is necessarily a $\pi$-clan. We exploit this $\pi$-clan structure to build the theory…

Category Theory · Mathematics 2026-02-06 Joseph Hua , Yiming Xu

A type theory is presented that combines (intuitionistic) linear types with type dependency, thus properly generalising both intuitionistic dependent type theory and full linear logic. A syntax and complete categorical semantics are…

Logic in Computer Science · Computer Science 2026-05-07 Matthijs Vákár

We will give a detailed account of why the simplicial sets model of the univalence axiom due to Voevodsky also models W-types. In addition, we will discuss W-types in categories of simplicial presheaves and an application to models of set…

Category Theory · Mathematics 2015-11-26 Benno van den Berg , Ieke Moerdijk

We construct a symmetric monoidal closed category of polynomial endofunctors (as objects) and simulation cells (as morphisms). This structure is defined using universal properties without reference to representing polynomial diagrams and is…

Logic in Computer Science · Computer Science 2015-07-01 Hyvernat Pierre

A convenient framework to treat massless two-dimensional scattering theories has been established by Buchholz. In this framework, we show that the asymptotic algebra and the scattering matrix completely characterize the given theory under…

Mathematical Physics · Physics 2017-09-26 Yoh Tanimoto