Kahler-Einstein Metrics on Fano Varieties

Geometric shapes can be either smooth or singular. Smooth ones have been studied effectively by the calculus, while singular geometric shapes are much more difficult to study in general although they appear with abundance in the world around us. One method to understand singular shapes is by measuring distances between their points. To do that, the best way is to use the so-called Einstein structures, which originate from general relativity. In this project, the investigator plans to study Einstein structures on a class of geometric shapes called algebraic varieties, which are central objects in many branches of mathematics. This study will allow us to measure distances and reveal certain mysterious structures of algebraic varieties. This project requires combinations of many techniques and will bring experts from different fields to interact. Its outcome will have potential applications in the development of several theories, including canonical metrics in differential geometry, stability theory in algebraic geometry, and string theory in mathematical physics. The investigator will study the Yau-Tian-Donaldson conjecture about the equivalence of K-stability and the existence of Kahler-Einstein metrics on singular Fano varieties. This requires new strategies to overcome difficulties due to the presence of singularities. The investigator has introduced a new process, the minimization of normalized volumes, for detecting local geometries of algebraic singularities. On the algebraic side, the investigator will continue his research on the K-stability of Fano varieties by studying minimization of normalized volumes and applying deep techniques of the minimal model program from algebraic geometry. This could lead to new criteria for the K-stability of singular varieties. On the analytic side, the investigator will apply various newly-developed techniques, including a variational approach via pluripotential theory, a priori estimates for singular complex Monge-Ampere equations, Cheeger-Colding-Tian's regularity theory from metric geometry, algebraic structures on Gromov-Hausdorff limits, and asymptotical analysis of singular metrics. The combination of these techniques will be effective in solving Kahler-Einstein equations on singular varieties. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.