2 4 Ja n 20 07 Remarks on surfaces with c 21 = 2 χ − 1 having non - trivial 2 - torsion
نویسنده
چکیده
We will show that any complex minimal surface of general type with c1 = 2χ− 1 having non-trivial 2-torsion divisors, where c 2 1 and χ are the first Chern number and the Euler characteristic of the structure sheaf respectively, has the Euler characteristic χ not exceeding 4. We will also give a complete description for the surfaces of the case χ = 4.
منابع مشابه
Automorphisms of Fiber Surfaces of Genus 2, Inducing the Identity in Cohomology
Let S be a complex non-singular projective surface of general type with a genus 2 fibration and χ(OS) ≥ 5. Let G ⊂ AutS be a non-trivial subgroup of automorphisms of S, inducing trivial actions on Hi(S,Q) for all i. Then |G| = 2, K2 S = 4χ(OS) and q(S) = 1. Examples of such surfaces are given.
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تاریخ انتشار 2007