论文标题
计数卡拉比(Calabi-Yau)4倍的滑轮,我
Counting sheaves on Calabi-Yau 4-folds, I
论文作者
论文摘要
Borisov-Joyce使用派生的差别几何形状,在4倍4倍的稳定束带的紧凑型模量空间上构建了一个真实的虚拟周期。 我们构建一个代数虚拟周期。一个关键步骤是将Edidin-Graham的Square root Euler类定位,以$ SO(R,\ Mathbb C)$捆绑在各向同性部分的零基因座上,或者是在同型锥的支持下。 我们证明了一个圆环定位公式,使不变式可计算,并在固定基因座紧凑时将其扩展到非划界情况。 我们通过定义$ k $ k $ - 理论的方形欧拉类及其本地化版本来提供$ k $ - 理论的改进。 在续集中,我们证明了我们的不变式繁殖Borisov-Joyce。
Borisov-Joyce constructed a real virtual cycle on compact moduli spaces of stable sheaves on Calabi-Yau 4-folds, using derived differential geometry. We construct an algebraic virtual cycle. A key step is a localisation of Edidin-Graham's square root Euler class for $SO(r,\mathbb C)$ bundles to the zero locus of an isotropic section, or to the support of an isotropic cone. We prove a torus localisation formula, making the invariants computable and extending them to the noncompact case when the fixed locus is compact. We give a $K$-theoretic refinement by defining $K$-theoretic square root Euler classes and their localised versions. In a sequel we prove our invariants reproduce those of Borisov-Joyce.