Rotation minimizing frames and spherical curves in simply isotropic and pseudo-isotropic 3-spaces
نویسندگان
چکیده
منابع مشابه
Rationally isotropic quadratic spaces are locally isotropic
Let R be a regular local ring, K its field of fractions and (V, φ) a quadratic space over R. In the case of R containing a field of characteristic zero we show that if (V, φ)⊗R K is isotropic over K, then (V, φ) is isotropic over R. 1 Characteristic zero case 1.0.1 Theorem (Main). Let R be a regular local ring, K its field of fractions and (V, φ) a quadratic space over R. Suppose R contains a f...
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The results of the present article extend the results of [Pa]. The main result of the article is Theorem 1.1 below. The proof is based on a moving lemma from [LM], a recent improvement due to O. Gabber of de Jong’s alteration theorem, and the main theorem of [PR]. A purity theorem for quadratic spaces is proved as well in the same generality as Theorem 1.1, provided that R is local. It generali...
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ژورنال
عنوان ژورنال: Tamkang Journal of Mathematics
سال: 2020
ISSN: 2073-9826,0049-2930
DOI: 10.5556/j.tkjm.51.2020.2960