On Skew Loops, Skew Branes and Quadratic Hypersurfaces
نویسندگان
چکیده
منابع مشابه
On skew loops, skew branes and quadratic hypersurfaces
A skew brane is an immersed codimension 2 submanifold in affine space, free from pairs of parallel tangent spaces. Using Morse theory, we prove that a skew brane cannot lie on a quadratic hypersurface. We also prove that there are no skew loops on embedded ruled developable discs in 3-space. MSC: 53A05, 53C50, 58E05
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Let $alpha$ be an endomorphism and $delta$ an $alpha$-derivationof a ring $R$. In this paper we study the relationship between an$R$-module $M_R$ and the general polynomial module $M[x]$ over theskew polynomial ring $R[x;alpha,delta]$. We introduce the notionsof skew-Armendariz modules and skew quasi-Armendariz modules whichare generalizations of $alpha$-Armendariz modules and extend thecla...
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ژورنال
عنوان ژورنال: Moscow Mathematical Journal
سال: 2003
ISSN: 1609-3321,1609-4514
DOI: 10.17323/1609-4514-2003-3-2-681-690