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Isomorphisms of Orlicz spaces

  • Seyyed Mohammad Tabatabaie EMAIL logo and Mahdi Latifpour
Published/Copyright: November 11, 2022

Abstract

In this paper, we provide some isomorphism preserving conditions for (weighted) Orlicz spaces, and as a main result, it is proved that if there exist a bicontinuous linear operator T : L w 1 Φ ( G 1 ) L w 2 Φ ( G 2 ) and a mapping a ( ξ ( a ) , h ( a ) ) from G 1 to × G 2 with T λ a = ξ ( a ) λ h ( a ) T for all a G 1 , then G 1 and G 2 are isomorphic, where Φ is a Δ 2 -regular Young function, G 1 and G 2 are locally compact groups and w 1 and w 2 are weight functions. Also, for a class of Young functions Φ, we show that if C V Φ ( G 1 ) and CV Φ ( G 2 ) are isometrically isomorphic, then G 1 and G 2 are isomorphic, CV Φ ( G i ) is the space of all convolution operators on the Orlicz space L Φ ( G i ) for i = 1 , 2 .

MSC 2010: 46E30; 43A22

Communicated by Siegfried Echterhoff


Acknowledgements

The authors would like to thank the referee of this paper for helpful remarks and suggestions to improve this paper.

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Received: 2022-02-11
Revised: 2022-08-30
Published Online: 2022-11-11
Published in Print: 2023-01-01

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