Abstract
Column closed pattern subgroups U of the finite upper unitriangular groups U n (q) are defined as sets of matrices in U n (q) having zeros in a prescribed set of columns besides the diagonal ones. We explain Jedlitschky's construction of monomial linearisation in his thesis and apply this to ℂU yielding a generalisation of Yan's coadjoint cluster representations. Then we give a complete classification of the resulting supercharacters, by describing the resulting orbits and determining the Hom-spaces between orbit modules.
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Acknowledgements
This work was supported by National Natural Science Foundation of China (Grant No. 11601338) and the German Research Foundation, Priority Programme Deutsche Forschungsgemeinschaft- Schwerpunktsprogramm Darstellungstheorie 1388 in Representation Theory (Grant No. 99028426). In addition, The authors thank the referees for interesting comments and valuable suggestions.
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Guo, Q., Dipper, R. On monomial linearisation and supercharacters of pattern subgroups. Sci. China Math. 61, 227–252 (2018). https://doi.org/10.1007/s11425-017-9213-x
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DOI: https://doi.org/10.1007/s11425-017-9213-x