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Character triples and relative defect zero characters

  • Junwei Zhang , Lizhong Wang and Ping Jin EMAIL logo
Published/Copyright: February 27, 2025

Abstract

Given a character triple ( G , N , ΞΈ ) , which means that 𝐺 is a finite group with N ⁒ ⊲ ⁒ G and ΞΈ ∈ Irr ⁑ ( N ) is 𝐺-invariant, we introduce the notion of a πœ‹-quasi-extension of πœƒ to 𝐺, where πœ‹ is the set of primes dividing the order of the cohomology element [ ΞΈ ] G / N ∈ H 2 ⁒ ( G / N , C Γ— ) associated with the character triple, and then we establish the uniqueness of such an extension in the normalized case. As an application, we use the πœ‹-quasi-extension of πœƒ to construct a bijection from the set of πœ‹-defect zero characters of G / N onto the set of relative πœ‹-defect zero characters of 𝐺 over πœƒ. Our results generalize the related theorems of M. Murai and of G. Navarro.

Award Identifier / Grant number: 12431001

Award Identifier / Grant number: 12171289

Funding statement: This work was supported by the NSF of China (Nos. 12431001, 12171289).

Acknowledgements

The authors are grateful to the referee for valuable comments and suggestions that greatly improve the exposition of the paper, and to Professor Jiping Zhang for his guidance and encouragement.

  1. Communicated by: Hung Tong-Viet

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Received: 2024-08-23
Revised: 2025-01-18
Published Online: 2025-02-27
Published in Print: 2025-07-01

Β© 2025 Walter de Gruyter GmbH, Berlin/Boston

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