Skip to main content
Log in

On some algebras diagonalized by M-bases of ℓ2

  • Published:
Integral Equations and Operator Theory Aims and scope Submit manuscript

Abstract

We study reflexive algebrasA whose invariant lattices LatA are generated by M-bases of ℓ2. Examples are given whereA differs from ℱ (ℱ being the rank one subalgebra ofA), and where ℱ together with the identity I is not strongly dense inA. For M-bases in a special class, we characterize the cases when they are strong, and also when the identity I is the ultraweak limit of a sequence of contractions in ℱ. We show that this holds provided that I is approximable by compact operators inA at any two points of ℓ2. We show that the spaceA+ℒ* (where ℒ is the annihilator of ℱ) is ultraweakly dense in ℬ(ℓ2), and characterize the M-bases in this class for which the sum is direct. We give a class of automorphisms ofA which are strongly continuous but not spatial.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  • [ALL] S. ARGYROS, M. LAMBROU, W. E. LONGSTAFF, Atomic Boolean Subspace Lattices and applications to the theory of Bases, Memoirs AMS, (91), 445, May 1991.

  • [AKL] M. ANOUSSIS, A. KATAVOLOS, M. S. LAMBROU, On the Reflexive algebra with two invariant subspaces, preprint.

  • [AS] E. AZOFF, H. SHEHADA, Algebras generated by mutually orthogonal idempotents, J. Operator Theory, to appear.

  • [E] J. A. ERDOS, Reflexivity for subspace maps and linear spaces of Operators, Proc. London Math. Soc. (3)52 (1986), 582–900.

    Google Scholar 

  • [EL] J. A. ERDOS, W. E. LONGSTAFF, Commuting families of operators of rank 1, Proc. London Math. Soc. 3 (44) 1982, 161–177.

    Google Scholar 

  • [GL] F. GILFEATHER, D. LARSON, Structure in reflexive subspace lattices, J. London Math. Soc. (2),26 (1982), 117–131.

    Google Scholar 

  • [K] E. KATSOULIS,Semisimplicity and Triangular Integration in Operator Algebras, PhD Thesis (in Greek), Athens Univ. (1989).

  • [KK] A. KATAVOLOS, E. KATSOULIS, Semisimplicity in operator algebras and subspace lattices, J. Lon. Math. Soc. (2)42 (1990), 365–372.

    Google Scholar 

  • [KLL] A. KATAVOLOS, M. S. LAMBROU, W. E. LONGSTAFF, The Decomposability of Operators relative to two subspaces, Studia Math., to appear.

  • [LA1] M. S. LAMBROU, Approximants, Commutants and Double commutants in normed algebras, J. London Math. Soc. (2)25 (1982), 499–512.

    Google Scholar 

  • [LA2] M. S. LAMBROU, Automatic continuity and Implementation of homomorphisms, preprint.

  • [LO1] W. E. LONGSTAFF, Strongly reflexive lattices, J. London Math. Soc. (2)11 (1975) 491–498.

    Google Scholar 

  • [LO2] W. E. LONGSTAFF, Operators of rank one in reflexive algebras, Canad. Journal Math.28 (1976), 19–23.

    Google Scholar 

  • [LW] D. LARSON, W. WOGEN, Reflexivity properties of T⊕O, J. Functional Analysis,92 (1990) 448–467.

    Google Scholar 

  • [LS] A. I. LOGINOV, G. S. SULMAN, Hereditary and intermediate reflexivity of W* algebras, Math. USSR-Izv.9 (1975) 1189–1201.

    Google Scholar 

  • [R] J. R. RINGROSE, On some algebras of operators II, Proc. Lon. Math. Soc. (3)16 (1966), 385–402.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Katavolos, A., Lambrou, M.S. & Papadakis, M. On some algebras diagonalized by M-bases of ℓ2 . Integr equ oper theory 17, 68–94 (1993). https://doi.org/10.1007/BF01322547

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF01322547

MSC

Navigation