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arXiv · 1010.3215

Pfister's theorem fails in the Hermitian case

John P. D'Angelo·Jiri Lebl
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Abstract

We show that the Hermitian analogue of a famous result of Pfister fails. To do so we provide a Hermitian symmetric polynomial $r$ of total degree 2d such that any non-zero multiple of it cannot be written as a Hermitian sum of squares with fewer than $d+1$ squares.

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John P. D'Angelo, Jiri Lebl. 2010-10-15. Pfister's theorem fails in the Hermitian case. https://doi.org/10.1090/s0002-9939-2011-10841-4

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