A Note on Essentially Left ϕ-Contractible Banach Algebras

Document Type : Research Paper

Authors

Ilam University

Abstract

In this note, we show that [11, Corollary 3.2] is not always true. In fact, we characterize essential left ϕ-contractibility of group algebras in terms of compactness of its related locally compact group. Also, we show that for any compact commutative group G, L2(G) is always essentially left ϕ-contractible. We discuss the essential left ϕ-contractibility of some Fourier algebras.

Keywords


  1. M. Alaghmandan, R. Nasr Isfahani and M. Nemati, Character amenability and contractibility of abstract Segal algebras, Bull. Austral. Math. Soc., 82: 274–281, (2010).
  2. F. Ghahramani and R.J. Loy, Generalized notions of amenability, J. Func. Anal., 208: 229–260, (2004).
  3. E. Hewitt and K.A. Ross, Abstract Harmonic Analysis I, Springer-Verlag, Berlin, (1963).
  4. E. Kaniuth and A.T. Lau, Fourier and Fourier Stieltjes Algebras on Locally Compact Groups, Amer. Math. Soc., Vol 231, (2018).
  5. E. Kaniuth, A.T. Lau and J. Pym, On ϕ-amenability of Banach algebras, Math. Proc. Cambridge Philos. Soc., 144: 85–96, (2008).
  6. R. Nasr Isfahani and M. Nemati, Essential character amenability of Banach algebras, Bull. Austral. Math. Soc., 84: 372–386, (2011).
  7. R. Nasr Isfahani and S. Soltani Renani, Character contractibility of Banach algebras and homological properties of Banach modules, Studia Math., 202(3): 205–225, (2011).
  8. M. Nemati, Some homological properties of Banach algebras associated with locally compact groups, Colloq. Math., 139: 259–271, (2015).
  9. W. Rudin, Fourier Analysis on Groups, Interscience Publishers, New York - London, (1962).
  10. V. Runde, Lectures on amenability, Springer, New York, (2002).
  11. R. Sadheghi Nahrekhalaji, Essential character contractibility for Banach algebras,U.P.B. Sci. Bull., Series A., 81(2): 165–176, (2019).
  12. M. Sangani Monfared, Character amenability of Banach algebras, Math. Proc. Camb. Phil. Soc., 144: 697-706, (2008).
  13. Y. Zhang, Nilpotent ideals in a class of Banach algebras, Proc. Amer. Math. Soc., 127(11): 3237-3242, (1999).