Positivstellensätze for real function algebras
نویسندگان
چکیده
منابع مشابه
Positivstellensätze for Real Function Algebras
We look for algebraic certificates of positivity for functions which are not necessarily polynomial functions. Similar questions were examined earlier by Lasserre and Putinar and by Putinar in [8, Proposition 1] and [14, Theorem 2.1]. We explain how these results can be understood as results on hidden positivity: The required positivity of the functions implies their positivity when considered ...
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Introduction. By a function algebra I shall mean a collection A of complex-valued functions on a set X such that the (pointwise) sum and the product of two functions in A are again in A. We shall always suppose that A contains the constant functions so that A becomes an algebra with unit over the field of complex numbers. A function algebra A is called self-ad joint if the complex conjugate of ...
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ژورنال
عنوان ژورنال: Mathematische Zeitschrift
سال: 2011
ISSN: 0025-5874,1432-1823
DOI: 10.1007/s00209-010-0831-1