Analytic surface germs with minimal Pythagoras number
نویسنده
چکیده
We determine all complete intersection surface germs whose Pythagoras number is 2, and find they are all embedded in R and have the property that every positive semidefinite analytic function germ is a sum of squares of analytic function germs. In addition, we discuss completely these properties for mixed surface germs in R. Finally, we find in higher embedding dimension three different families with these same properties.
منابع مشابه
On the Pythagoras numbers of real analytic set germs
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