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Search: MSC category 14J26 ( Rational and ruled surfaces )

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1. CJM 2011 (vol 64 pp. 123)

Lee, Jae-Hyouk
 Gosset Polytopes in Picard Groups of del Pezzo Surfaces In this article, we study the correspondence between the geometry of del Pezzo surfaces $S_{r}$ and the geometry of the $r$-dimensional Gosset polytopes $(r-4)_{21}$. We construct Gosset polytopes $(r-4)_{21}$ in $\operatorname{Pic} S_{r}\otimes\mathbb{Q}$ whose vertices are lines, and we identify divisor classes in $\operatorname{Pic} S_{r}$ corresponding to $(a-1)$-simplexes ($a\leq r$), $(r-1)$-simplexes and $(r-1)$-crosspolytopes of the polytope $(r-4)_{21}$. Then we explain how these classes correspond to skew $a$-lines($a\leq r$), exceptional systems, and rulings, respectively. As an application, we work on the monoidal transform for lines to study the local geometry of the polytope $(r-4)_{21}$. And we show that the Gieser transformation and the Bertini transformation induce a symmetry of polytopes $3_{21}$ and $4_{21}$, respectively. Categories:51M20, 14J26, 22E99

2. CJM 2008 (vol 60 pp. 64)

Daigle, Daniel
 Classification of Linear Weighted Graphs Up to Blowing-Up and Blowing-Down We classify linear weighted graphs up to the blowing-up and blowing-down operations which are relevant for the study of algebraic surfaces. Keywords:weighted graph, dual graph, blowing-up, algebraic surfaceCategories:14J26, 14E07, 14R05, 05C99

3. CJM 2007 (vol 59 pp. 1098)

Rodrigues, B.
 Ruled Exceptional Surfaces and the Poles of Motivic Zeta Functions In this paper we study ruled surfaces which appear as an exceptional surface in a succession of blowing-ups. In particular we prove that the $e$-invariant of such a ruled exceptional surface $E$ is strictly positive whenever its intersection with the other exceptional surfaces does not contain a fiber (of $E$). This fact immediately enables us to resolve an open problem concerning an intersection configuration on such a ruled exceptional surface consisting of three nonintersecting sections. In the second part of the paper we apply the non-vanishing of $e$ to the study of the poles of the well-known topological, Hodge and motivic zeta functions. Categories:14E15, 14J26, 14B05, 14J17, 32S45

4. CJM 2004 (vol 56 pp. 1145)

Daigle, Daniel; Russell, Peter
 On Log $\mathbb Q$-Homology Planes and Weighted Projective Planes We classify normal affine surfaces with trivial Makar-Limanov invariant and finite Picard group of the smooth locus, realizing them as open subsets of weighted projective planes. We also show that such a surface admits, up to conjugacy, one or two $G_a$-actions. Categories:14R05, 14J26, 14R20