Witt Equivalence of Rings of Regular Functions

• Autorzy: Przemysław Koprowski
• Języki publikacji: EN

Abstrakty

EN

In this paper we show that the rings of regular functions on two real algebraic curves over the same real closed field are Witt equivalent (i.e. their Witt rings are isomorphic) if and only if the curves have the same numer of semi-algebraically connected components. Moreover, in the second part of the paper, we prove that every strong isomorphism of Witt rings of rings of regular functions can be extended to an isomorphism of Witt rings of fields of rational functions. This extension is not unique, though. (original abstract)

Słowa kluczowe

EN

Mathematics; Mathematic calculations; Mathematical functions; Isomorphism

PL

Matematyka; Obliczenia matematyczne; Funkcje matematyczne; Izomorfizm

• Czasopismo: Annales Mathematicae Silesianae
• Rocznik: 2008
• Tom: 22
• Strony: 45--57

Twórcy

autor

Przemysław Koprowski

• Silesian University, Poland

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