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Register a new userSums of squares in function fields over Henselian local fields
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Authors
Olivier Benoist
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We give upper bounds for the level and the Pythagoras number of function fields over fraction fields of integral Henselian excellent local rings. In particular, we show that the Pythagoras number of $mathbb{R}((x_1,dots,x_n))$ is $leq 2^{n-1}$, which answers positively a question of Choi, Dai, Lam and Reznick.
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This is the final version, to appear in Commentarii Mathematici Helvetici.
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