On compact action in JB-algebras

Geometric Unitaries in Jb-algebras

In this article, we study geometric unitaries of JB-algebras (in particular, self-adjoint parts of C∗-algebras). We will show that the geometric unitaries of a JB algebra are precisely those central algebraic unitaries (or central symmetries). We will also show that the group of surjective isometries on a JB-algebra A (with point-norm topology) is the semi-direct product of the canonical action...

CHEBYSHEV SUBALGEBRAS OF JB-ALGEBRAS

In this note, we characterize Chebyshev subalgebras of unital JB-algebras. We exhibit that if B is Chebyshev subalgebra of a unital JB-algebra A, then either B is a trivial subalgebra of A or A= H R .l, where H is a Hilbert space

On Continuous Fields of Jb-algebras

We introduce and study continuous fields of JB-algebras (which are real non-associate analogues of C*-algebras). In particular, we show that for the universal enveloping C*-algebra C∗ u (B) for the JB-algebra B defined by a continuous field of JB-algebras At, t ∈ T, on a locally compact space T there exists a decomposition of C∗ u (B) into a continuous field of C*-algebras C∗ u (At), t ∈ T, on ...

Automatic Continuity of Higher Derivations on JB*-Algebras

Asymmetric Decompositions of Vectors in Jb∗-algebras

By investigating the extent to which variation in the coefficients of a convex combination of unitaries in a unital JB-algebra permits that combination to be expressed as convex combination of fewer unitaries of the same algebra, we generalise various results of R. V. Kadison and G. K. Pedersen. In the sequel, we shall give a couple of characterisations of JB-algebras of tsr