Unit Group  of the Group Algebra $\mathbb{F}_qGL(2,7)$

Authors

  • Namatchivayam Umapathy Sivaranjani SRM Institute of Science and Technology
  • Elumalai Nandakumar SRM Institute of Science and Technology
  • Gaurav Mittal Defence Research and Development Organization
  • Rajendra Kumar Sharma Indian Institute of Technology Delhi

DOI:

https://doi.org/10.52737/18291163-2024.16.3-1-14

Keywords:

Unit Group, Group Algebra, General Linear Group, Wedderburn Decomposition

Abstract

In this paper, we consider the general linear group $GL(2, 7)$ of $2 \times 2$ invertible matrices over the finite field of order $7$ and compute the unit group of the semisimple group algebra $\mathbb{F}_qGL(2,7)$, where $\mathbb{F}_q$ is a finite field. For the computation of the unit group, we need the Wedderburn decomposition of $\mathbb{F}_qGL(2,7)$, which is determined by first computing the Wedderburn decomposition of the group algebra $\mathbb{F}_q(PSL(3, 2)\rtimes C_2)$. Here $PSL(3,2)$ is the projective special linear group of degree 3 over a finite field of 2 elements.

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Published

2024-03-13

How to Cite

Unit Group  of the Group Algebra $\mathbb{F}_qGL(2,7)$. (2024). Armenian Journal of Mathematics, 16(3), 1-14. https://doi.org/10.52737/18291163-2024.16.3-1-14