Note on Tudicula inermis &c.

A Note on Spectrum Preserving Additive Maps on C*-Algebras

Mathieu and Ruddy proved that if be a unital spectral isometry from a unital C*-algebra Aonto a unital type I C*-algebra B whose primitive ideal space is Hausdorff and totallydisconnected, then is Jordan isomorphism. The aim of this note is to show that if be asurjective spectrum preserving additive map, then is a Jordan isomorphism without the extraassumption totally disconnected.

a note on finite c-tidy groups

let $g$ be a group and $x in g$‎. ‎the cyclicizer of $x$ is defined to be the subset $cyc(x)=lbrace y in g mid langle x‎, ‎yrangle ; {rm is ; cyclic} rbrace$‎. ‎$g$ is said to be a tidy group if $cyc(x)$ is a subgroup for all $x in g$‎. ‎we call $g$ to be a c-tidy group if $cyc(x)$ is a cyclic subgroup for all $x in g setminus k(g)$‎, ‎where $k(g)$ is the intersection of all the cyclicizers in ...

A Note on Approximately Divisible C∗-algebras

Abstract: Let A be a separable, unital, approximately divisible C∗-algebra. We show that A is generated by two self-adjoint elements and the topological free entropy dimension of any finite generating set of A is less than or equal to 1. In addition, we show that the similarity degree of A is at most 5. Thus an approximately divisible C∗-algebra has an affirmative answer to Kadison’s similarity...

A Note on Spectral Illusions, &c.

In the last number of tlie Journal of Psychological Medicine there is an article by Dr. W. A. F. Browne, a well known and much respected authority, on " Second-sight, or Deuteroscopia." To write a criticism, or commentary, on the article is no part of my present purpose. Indeed, fascinating as the subject is, I should not have been tempted to meddle with it at all but for one of the anecdotes r...

A Note on a Question of C .