Lawvere theories provide a categorical formulation of the algebraic theories from universal algebra. Freyd categories are categorical models of first-order effectful programming languages. The notion of sound limit doctrine has been used to classify accessible categories. We provide a definition of Lawvere theory that is enriched in a closed category that is locally presentable with respect to ...

Theories of rational belief revision recently proposed by Gärdenfors and Nebel illuminate many important issues but impose unnecessarily strong standards for correct revisions and make strong assumptions about what information is available to guide revisions. We reconstruct these theories according to an economic standard of rationality in which preferences are used to select among alternative ...

We introduce the concept of Frobenius theory as a generalisation of Lawvere’s functorial semantics approach to categorical universal algebra. Whereas the universe for models of Lawvere theories is the category of sets and functions, or more generally cartesian categories, Frobenius theories take their models in the category of sets and relations, or more generally in cartesian bicategories.

Magnetic BPS string solutions preserving quarter of supersymmetry are obtained for all abelian gauged d = 5 N = 2 supergravity theories coupled to vector supermultiplets. Due to a “generalised Dirac quantization” condition satisfied by the minimized magnetic central charge, the string metric takes a universal form for all five dimensional gauged theories. e-mail: [email protected], [email protected]....

This paper is to construct unstable, Morita stable and stable bivariant algebraic Kasparov K-theory spectra of k-algebras. These are shown to be homotopy invariant, excisive in each variable K-theories. We prove that the spectra represent universal unstable, Morita stable and stable bivariant homology theories respectively. 2010 Mathematics Subject Classification: 19D99, 19K35, 55P42

A critical study of the arguments for and against the hypothesis that human beings are born with an innate universal grammar, with some brief discussions of alternative theories.

The universal theories of integral domains and of ordered integral domains which have the amalgamation property are characterized via their existentially complete models. The results of A. Macintyre, K. McKenna, and L. van den Dries on fields and ordered fields whose complete theories permit elimination of quantifiers are then derived as easy corollaries. A. Macintyre, K. McKenna, and L. van de...