Basic properties of certain class of non normal operators

Basic properties of certain class of non normal operators

Some properties of k-quasi-M-hyponormal are established in this paper. The ascent and an extension of thewell-known Fuglede Putnam's Theorem for such operators as well as other related results are also presented,which complete some results given in [7, 12].

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  • [1] P. Aiena, Fredholm and Local Spectral Theory with Applications to Multipliers, Kluwer Academic Publishers. (2004).
  • [2] S.C. Arora, R. Kumar, M-hyponormal operators, Yokohama Math. J. 28 (1980) 41-44.
  • [3] A. Bachir, F. Lombarkia, Fuglede-Putnam's Theorem for w-hyponormal operators, Math. Ineq. Appli. 12(4) (2012) 777-786.
  • [4] S. Jo, Y. Kim, E. Ko, On Fuglede-Putnam Properties, Positivity, (2015) DOI 10.1007 /s11117-015-0335-7.
  • [5] I.H. Kim, The Fuglede-Putnam Theorem for (p,k)-quasihyponormal operators, J. Ineq. Appl. (2006) ID 47481 1-7.
  • [6] F. Lombarkia, M. Amouch, Asymetric Fuglede-Putnam's Theorem for Operators Reduced by their Eigenspaces, Filomat 31:20 (2017) 6409-6417.
  • [7] S. Mecheri, On k-quasi-M-hyponormal operators, Math. Ineq. Appli. 16(3) (2013) 895-902.
  • [8] S. Mecheri, K. Tanahashi, A. Uchiyama, Fuglede-Putnam theorem for p-hyponormal operators or class Y operators, Bull. Korean Math. Soc. 43(4) (2006) 747-753.
  • [9] A. Nasli Bakir, S. Mecheri, Another version of Fuglede-Putnam theorem, Georg. Math. J. 16(3) (2009) 427-433.
  • [10] J.G. Stampfli, B.L. Wadhwa, An asymmetric Putnam-Fuglede theorem for dominant operators, Indiana Univ. Math. J. 25 (1976) 359-365.
  • [11] K. Tanahashi, On the converse of the Fuglede-Putnam's Theorem, Acta. Sci. Math. (Szeged) 43 (1981) 123-125.
  • [12] F. Zuo, S. Mecheri, Spectral properties of k-quasi-M-hyponormal operators, Complex Anal. Oper.Theory. (2017) DOI 10.1007/s11785-017-0686-0.
  • [13] F. Zuo, H. Zuo, Weyl-type theorems and k-quasi-M-hyponormal operators, J. Ineq. Appl. (2013) /2013/1/446 1-6.