A bridge connecting convex analysis and complex analysis and $L^2$-estimate of $d$ and $\bar\partial$
Fusheng Deng, Jinjin Hu, Weiwen Jiang, Xiangsen Qin
TL;DR
This work builds a principled bridge between convex analysis and complex analysis by transferring problems from convex domains in $\mathbb{R}^n$ to rotation-invariant settings on Reinhardt domains via tube domains and the exponential map. The authors develop and apply $L^2$-estimates for the $\bar{\partial}$-equation and the $d$-operator within this framework, obtaining both sharp extension results and curvature-positivity conclusions for direct-image bundles. Key contributions include a Berndtsson-style $L^2$-estimate on tube-type domains, an optimal $L^2$-extension theorem with explicit constants, and Nakano positivity results for direct images in families of circular/Reinhardt domains, with convex-domain corollaries. The results illuminate how complex-analytic techniques yield insights and tools for convex-analytic problems, potentially enabling new Brunn-Minkowski-type inequalities in real settings via complex-analytic methods.
Abstract
We propose a way to connect complex analysis and convex analysis. As applications, we derive some results about $L^2$-estimate for $d$-equation and prove some curvature positivity related to convex analysis from well known $L^2$-estimate for $\bar\partial$-equation or the results we prove in complex analysis.
