Fuglede-Putnam type commutativity theorems for EP operators

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Abstract

Fuglede-Putnam theorem is not true in general for EP operators on Hilbert spaces. We prove that under some
conditions the theorem holds good. If the adjoint operation is replaced by Moore-Penrose inverse in the theorem,
we get Fuglede-Putnam type theorem for EP operators – however proofs are totally different. Finally, interesting
results on EP operators have been proved using several versions of Fuglede-Putnam type theorems for EP
operators on Hilbert spaces.

Keywords:

Fuglede-Putnam theorem, Moore-Penrose inverse, EP operator

Mathematics Subject Classification:

Mathematics
  • P. Sam Johnson Department of Mathematical and Computational Sciences, National Institute of Technology Karnataka, Surathkal, Mangaluru 575 025, India. https://orcid.org/0000-0003-3461-5380
  • Vinoth A Department of Mathematics, St. Xavier’s College, Palayamkottai 627 002, India.
  • K. Kamaraj Department of Mathematics, University College of Engineering Arni, Anna University, Arni 632 326, India.
  • Pages: 709-714
  • Date Published: 01-01-2021
  • Vol. 9 No. 01 (2021): Malaya Journal of Matematik (MJM)

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Published

01-01-2021

How to Cite

P. Sam Johnson, Vinoth A, and K. Kamaraj. “Fuglede-Putnam Type Commutativity Theorems for EP Operators”. Malaya Journal of Matematik, vol. 9, no. 01, Jan. 2021, pp. 709-14, https://www.malayajournal.org/index.php/mjm/article/view/1117.