Abstract
Let F be a field of characteristic different from 2 and V be a vector space over F. Let J: α → α J be a fixed involutory automorphism on F. In this paper we answer the following question: given an invertible linear map T: V → V, when does the vector space V admit a T-invariant nondegenerate J-hermitian, resp. J-skew-hermitian, form?
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Gongopadhyay, K., Mazumder, S. Existence of an invariant form under a linear map. Indian J Pure Appl Math 48, 211–220 (2017). https://doi.org/10.1007/s13226-017-0222-y
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DOI: https://doi.org/10.1007/s13226-017-0222-y