## The Fischer-Clifford matrices of a maximal subgroup of $Fi^{\prime }_{24}$

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- by Faryad Ali and Jamshid Moori
- Represent. Theory
**7**(2003), 300-321 - DOI: https://doi.org/10.1090/S1088-4165-03-00175-4
- Published electronically: July 29, 2003
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## Abstract:

The Fischer group $Fi_{24}^{\prime }$ is the largest sporadic simple Fischer group of order \[ 1255205709190661721292800 = 2^{21}.3^{16}.5^2.7^3.11.13.17.23.29 \;\;.\] The group $Fi_{24}^{\prime }$ is the derived subgroup of the Fischer $3$-transposition group $Fi_{24}$ discovered by Bernd Fischer. There are five classes of elements of order 3 in $Fi_{24}^{\prime }$ as represented in ATLAS by $3A$, $3B$, $3C$, $3D$ and $3E$. A subgroup of $Fi_{24}^{\prime }$ of order $3$ is called of type $3X$, where $X \in \{A,B,C,D,E \}$, if it is generated by an element in the class $3X$. There are six classes of maximal 3-local subgroups of $Fi_{24}^{\prime }$ as determined by Wilson. In this paper we determine the Fischer-Clifford matrices and conjugacy classes of one of these maximal 3-local subgroups $\bar {G} := N_{Fi_{24}^{\prime }}(\langle N\rangle ) \cong 3^7{\cdot }O_7(3)$, where $N \cong 3^7$ is the natural orthogonal module for $\bar {G}/N \cong O_7(3)$ with $364$ subgroups of type $3B$ corresponding to the totally isotropic points. The group $\bar {G}$ is a nonsplit extension of $N$ by $G \cong O_7(3)$.## References

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## Bibliographic Information

**Faryad Ali**- Affiliation: School of Mathematics, Statistics and I.T., University of Natal, Private Bag X 01, Scottsville, Pietermaritzburg 3209, South Africa
- ORCID: setImmediate$0.9265022794625328$2
**Jamshid Moori**- Affiliation: School of Mathematics, Statistics and I.T., University of Natal, Private Bag X 01, Scottsville, Pietermaritzburg 3209, South Africa
- Received by editor(s): August 29, 2002
- Received by editor(s) in revised form: April 7, 2003
- Published electronically: July 29, 2003
- Additional Notes: The first author was supported by a postgraduate bursary from the NRF(SA)

The second author was supported by a research grant from University of Natal and NRF(SA) - © Copyright 2003 American Mathematical Society
- Journal: Represent. Theory
**7**(2003), 300-321 - MSC (2000): Primary 20C15, 20D08, 20E22
- DOI: https://doi.org/10.1090/S1088-4165-03-00175-4
- MathSciNet review: 1993362