ﻻ يوجد ملخص باللغة العربية
Let $mathcal{C}$ be a finitely bicomplete category and $mathcal{W}$ a subcategory. We prove that the existence of a model structure on $mathcal{C}$ with $mathcal{W}$ as subcategory of weak equivalence is not first order expressible. Along the way we characterize all model structures where $mathcal{C}$ is a partial order and show that these are determined by the homotopy categories.
We prove that every 2-Segal space is unital.
Given a continuous monadic functor T in the category of Tychonov spaces for each discrete topological semigroup X we extend the semigroup operation of X to a right-topological semigroup operation on TX whose topological center contains the dense subs
In previous work we proved that, for categories of free finite-dimensional modules over a commutative semiring, linear compact-closed symmetric monoidal structure is a property, rather than a structure. That is, if there is such a structure, then it
For a commutative quantale $mathcal{V}$, the category $mathcal{V}-cat$ can be perceived as a category of generalised metric spaces and non-expanding maps. We show that any type constructor $T$ (formalised as an endofunctor on sets) can be extended in
We study abelian envelopes for pseudo-tensor categories with the property that every object in the envelope is a quotient of an object in the pseudo-tensor category. We establish an intrinsic criterion on pseudo-tensor categories for the existence of