## Isometric isomorphisms between Banach algebras related to locally compact groups

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- by F. Ghahramani, A. T. Lau and V. Losert PDF
- Trans. Amer. Math. Soc.
**321**(1990), 273-283 Request permission

## Abstract:

Let ${G_1}$, ${G_2}$ be locally compact groups. We prove in this paper that if $T$ is an isometric isomorphism from the Banach algebra ${\text {LUC}}{({G_1})^*}$ (the continuous dual of the Banach space of left uniformly continuous functions on ${G_1}$, equipped with Arens multiplication) onto ${\text {LUC}}{({G_2})^*}$, then $T$ maps $M({G_1})$ onto $M({G_2})$ and ${L^1}({G_1})$ onto ${L^1}({G_2})$. We also prove that any isometric isomorphism from ${L^1}{({G_1})^{**}}$ (second conjugate algebra of ${L^1}({G_1})$) onto ${L^1}{({G_2})^{**}}$ maps ${L^1}({G_1})$ onto ${L^1}({G_2})$.## References

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## Additional Information

- © Copyright 1990 American Mathematical Society
- Journal: Trans. Amer. Math. Soc.
**321**(1990), 273-283 - MSC: Primary 43A20; Secondary 43A10, 46J99
- DOI: https://doi.org/10.1090/S0002-9947-1990-1005079-2
- MathSciNet review: 1005079