Questions tagged [sketches]

Guitart states in "Toute theorie est algebrique et topologique" as Proposition 17 that the category $\mathbf{Sch}$ of schemes is the category of models of a large mixed sketch. Presumably, ...

$\newcommand\Sketch{\mathit{Sketch}}\newcommand\Set{\mathit{Set}} \DeclareMathOperator\Lim{Lim}\DeclareMathOperator\Colim{Colim}\DeclareMathOperator\Mod{Mod}\newcommand\mod{\operatorname{mod}}\...

I'm wondering if it's possible to find an universal construction for a general concept of action for (single-sorted?) finite product sketches, such that one of those is "acting" on the second in the ...

Let $C$ be a category. Roughly, a model of a (finite) limit sketch in $C$ is a functor $S \to C$ where $S$ small category with some specified (finite) cones which are sent to limits in $C$. $S$ itself ...

I think I'm in the process of understanding something very subtle here, and I could use an expert's double check. So basically, my question is whether what I write is correct. (Non-finitary) GATs, ...

In Sketches: Outline with References 4.3, Wells cites the result that sketches are sketchable by a finite limit sketch. I can't find the Burroni 1970a paper, and I am having a lot of trouble with Lair ...