Real divisors algebraically equivalent to zero
نویسندگان
چکیده
منابع مشابه
Equivalent Birational Embeddings Ii: Divisors
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Let R be a commutative ring with unity. The set Z(R) of zero-divisors in a ring does not possess any obvious algebraic structure; consequently, the study of this set has often involved techniques and ideas from outside algebra. Several recent attempts, among them [2], [3] have focused on studying the so-called zero-divisor graph ΓR, whose vertices are the zero-divisors of R, with xy being an ed...
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Let G be a graph, χ(G) be the minimal number of colors which can be assigned to the vertices of G in such a way that every two adjacent vertices have different colors and ω(G) to be the least upper bound of the size of the complete subgraphs contained in G. It is well-known that χ(G) ≥ ω(G). Beck in [6] conjectured that χ(Γ0(R)) = ω(Γ0(R)) if ω(Γ0(R)) < ∞, where Γ0(R) is a graph associated to a...
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ژورنال
عنوان ژورنال: Mathematical Research Letters
سال: 2003
ISSN: 1073-2780,1945-001X
DOI: 10.4310/mrl.2003.v10.n6.a8