A note on “Extensional PERs”

A Note On Logical PERs and ReducibilityLogical Relations

We prove a general theorem for establishing properties expressed by binary relations on typed ((rst-order)-terms, using a variant of the reducibility method and logical PERs. As an application, we prove simultaneously that-reduction in the simply-typed-calculus is strongly normalizing, and that the Church-Rosser property holds (and similarly for-reduction).

On Simple and Extensional

The notions of simplicity and extensionality for coalgebras are generalized beyond Set and a study of the internal dynamics of extensional coalgebras yields the notion of unitary coalgebras. In some cases, unitary coalgebras include extensional ones. Under some reasonable circumstances, both notions of simplicity and extensionality agree. Other extensions of simplicity and extensionality are ∗−...

A note on vague graphs

In this paper, we introduce the notions of product vague graph, balanced product vague graph, irregularity and total irregularity of any irregular vague graphs and some results are presented. Also, density and balanced irregular vague graphs are discussed and some of their properties are established. Finally we give an application of vague digraphs.

A note on lifting projections

Suppose $pi:mathcal{A}rightarrow mathcal{B}$ is a surjective unital $ast$-homomorphism between C*-algebras $mathcal{A}$ and $mathcal{B}$, and $0leq aleq1$ with $ain  mathcal{A}$. We give a sufficient condition that ensures there is a proection $pin mathcal{A}$ such that $pi left( pright) =pi left( aright) $. An easy consequence is a result of [L. G. Brown and G. k. Pedersen, C*-algebras of real...

A Note on Finsler Modules