arXiv math/05042292005-04math.CVmath.AG

Geometry of Hermitian Algebraic Functions. Quotients of Squared Norms

Dror Varolin

备注：: Major revision. Some errors in the proof corrected, and other incorrect results removed, but the main result remains the same

英文摘要：

Hermitian algebraic functions were introduced by Catlin and D'Angelo under the name of "globalizable metrics". Catlin and D'Angelo proved that any Hermitian algebraic function without non-trivial zeros is a quotient of squared norms, thus giving an answer to a Hermitian analogue of Hilbert's 17th problem in the non-degenerate case. The result was independently proved somewhat earlier by D. Quillen in a special case, and using different methods. In this paper, we characterize all Hermitian algebraic functions that are quotients of squared norms.

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