Abstract
Let K be a field of characteristic not 2 and A a central simple algebra with an involution σ. A result of Mahmoudi provides an upper bound for the u-invariants of hermitian forms and skew-hermitian forms over (A, σ) in terms of the u-invariant of K. In this paper we give a different upper bound when A is a tensor product of quaternion algebras and σ is a the tensor product of canonical involutions. We also show that our bounds are sharper than those of Mahmoudi.
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PARIHAR, S.S., SURESH, V. On the u-invariant of hermitian forms. Proc Math Sci 123, 303–313 (2013). https://doi.org/10.1007/s12044-013-0131-x
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DOI: https://doi.org/10.1007/s12044-013-0131-x