اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدOn the slope conjecture of Barja and Stoppino for fibred surfaces
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Let $f:,S to B$ be a locally non-trivial relatively minimal fibration of genus $ggeq 2$ with relative irregularity $q_f$. It was conjectured by Barja and Stoppino that the slope $lambda_fgeq frac{4(g-1)}{g-q_f}$. We prove the conjecture when $q_f$ is small with respect to $g$; we also construct counterexamples when $g$ is odd and $q_f=(g+1)/2$.
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