Which linear maps of the disk algebra are multiplicative

Multiplicative Maps on Ideals of Operators Which Are Local Automorphisms

We present the following reflexivity-like result concerning the automorphism group of the C∗-algebra B(H), H being a separable Hilbert space. Let φ : B(H) → B(H) be a multiplicative map (no linearity or continuity is assumed) which can be approximated at every point by automorphisms of B(H) (these automorphisms may, of course, depend on the point) in the operator norm. Then φ is an automorphism...

Multilinear forms which are products of linear forms

The conditions under which, multilinear forms (the symmetric case and the non symmetric case),can be written as a product of linear forms, are considered. Also we generalize a result due to S.Kurepa for 2n-functionals in a group G.

Linear Discrete Operators on the Disk Algebra

Let A be the disk algebra. In this paper we address the following question: Under what conditions on the points zk,n ∈ D do there exist operators Ln : A → A such that

Compact Endomorphisms of Certain Subalgebras of the Disk Algebra

Multiplicative bijective maps on standard operator algebras