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 investigate different notions of recognizability for a free monoid morphism σ : A∗ → B∗. Full recognizability occurs when each (aperiodic) point in BZ admits at most one tiling with words σ(a), a ∈ A. This is stronger than the classical notion of recognizability of a substitution σ : A∗ → A∗, where the tiling must be compatible with the language of the substitution. We show that if |A| = 2, ...

We present an approach to modeling computational calculi using higher category theory. Specifically we present a fully abstract semantics for the π-calculus. The interpretation is consistent with Curry-Howard, interpreting terms as typed morphisms, while simultaneously providing an explicit interpretation of the rewrite rules of standard operational presentations as 2-morphisms. One of the key ...

The aim of this note is to introduce the class of free geometries purely in terms of morphisms. Several classes of well-known matroid morphisms are characterized via the new concept. 2000 Mathematics Subject Classification. 05B35.

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.

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.

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 ...