activity
20152020
collaborators

8 papers

cs.LO2020

Internal -Categorical Models of Dependent Type Theory: Towards 2LTT Eating HoTT

Nicolai Kraus

Using dependent type theory to formalise the syntax of dependent type theory is a very active topic of study and goes under the name of "type theory eating itself" or "type theory…

math.LO2020

Coherence via Well-Foundedness: Taming Set-Quotients in Homotopy Type Theory

Nicolai Kraus, Jakob von Raumer

Suppose we are given a graph and want to show a property for all its cycles (closed chains). Induction on the length of cycles does not work since sub-chains of a cycle are not nec…

cs.LO2019

Shallow Embedding of Type Theory is Morally Correct

Ambrus Kaposi, András Kovács, Nicolai Kraus

There are multiple ways to formalise the metatheory of type theory. For some purposes, it is enough to consider specific models of a type theory, but sometimes it is necessary to r…

cs.LO2019

From Cubes to Twisted Cubes via Graph Morphisms in Type Theory

Gun Pinyo, Nicolai Kraus

Cube categories are used to encode higher-dimensional categorical structures. They have recently gained significant attention in the community of homotopy type theory and univalent…

math.LO2019

Path Spaces of Higher Inductive Types in Homotopy Type Theory

Nicolai Kraus, Jakob von Raumer

The study of equality types is central to homotopy type theory. Characterizing these types is often tricky, and various strategies, such as the encode-decode method, have been deve…

cs.LO2018

Free Higher Groups in Homotopy Type Theory

Nicolai Kraus, Thorsten Altenkirch

Given a type A in homotopy type theory (HoTT), we can define the free infinity-group on A as the loop space of the suspension of A+1. Equivalently, this free higher group can be de…