Morphisms are widely used in several branches of scienti c inquiry, but not so much economics. Nevertheless, many conceptual advan- tages the economic modeling from using a categorical setting exist. In this paper, we discuss why morphisms could be successfully injected into and, particular, that allomorphisms, i.e., structure- altering maps re-shape processes, can useful for letting economics ...

We give the necessary and suucient condition for a Riemannian foliation, of arbitrary dimension, locally generated by Killing elds to produce harmonic morphisms. Natural constructions of harmonic maps and morphisms are thus obtained.

In this paper we determine the ring structure of the Hochschild cohomology of truncated quiver algebras with the Yoneda product. On the one hand Locateli described the cohomology groups in terms of classes of pairs of paths using minimal resolutions. On the other hand, the Yoneda product has a nice description on the bar resolution as the usual cup product. Our first main result is the explicit...

We study the equality problem for infinite words obtained by iterating morphisms. In particular, we give a practical algorithm to decide whether or not two words generated by primitive morphisms are equal.

To every regular category $\mathcal{A}$ equipped with a degree function $\delta$ one can attach pseudo-abelian tensor $\mathcal{T}(\mathcal{A},\delta)$. We show that the generating objects of $\mathcal{T}$ decompose canonically as direct sum. In this paper we calculate morphisms, compositions morphisms and products summands. As special case recover original construction Deligne's $\operatorname...

We find a criterion for a morphism of coalgebras over a Barr-exact category to be effective descent and determine (effective) descent morphisms for coalgebras over toposes in some cases. Also, we study some exactness properties of endofunctors of arbitrary categories in connection with natural transformations between them as well as those of functors that these transformations induce between co...

The general topic of this thesis is the investigation of various notions of morphisms between logical deductive systems, motivated by the intuition that additional (categorical) structure is needed to model the interrelations of formal specifications. This general task necessarily involves considerations in various mathematical disciplines, some of which might be interesting in their own right ...

We give a complete characterization of the class of quasi-compact morphisms of schemes that are stable effective descent morphisms for the SCHEMESindexed category given by quasi-coherent sheaves of modules.

Throughout this note all rings are commutative, and A is a fixed ring. If S, T are graded A-algebras then the tensor product S ⊗A T becomes a graded A-algebra in a canonical way with the grading given by (TES,Lemma 13). That is, S ⊗A T is the coproduct of the morphisms of A-modules Sd ⊗A Te −→ S ⊗A T for d, e ≥ 0. The canonical morphisms p1 : S −→ S ⊗A T, p2 : T −→ S ⊗A T are then morphisms of ...