For a finite Blaschke product $B$, the von Neumann algebra $\mathcal{V}^*(B) = \{M_B, M_B^*\}'$ has been thoroughly studied,
where $M_B$ is the multiplication operator defined by $B$ on the Bergman space $L_a^2(\mathbb{D})$ over the unit disk $\mathbb{D}$. A key result establishes that the number of minimal projections in $\mathcal{V}^*(B)$ equals the number of components of the Riemann surface $ \mathcal{S}_B $ lying in $ \mathbb{D}^2 $. However, computing this integer for a given finite Blaschke product $ B$ remains nontrivial. Traditional methods typically rely on analyzing neighborhoods of the unit circle.
In contrast, our approach leverages the analytic continuations of $ B$ by examining its critical points. This reveals connections between function theory, operator theory, and complex geometry.
This research is a collaborative effort with Danni Guo, Shan Li, Shuaibing Luo.
黄寒松,华东理工大学数学学院教授,研究兴趣为函数空间上的算子理论,特别在Bergman空间上的乘法算子理论方面取得了一定的成果。2009年博士毕业于复旦大学数学科学学院,同年进入华东理工大学工作至今。2014.8-2015.8在美国范德堡大学访学,2016年在上海数学中心访问。在Proc. London Math. Soc.; J. Funct. Anal.; J. Geom. Anal.; Sci. China Math.等国内外学术期刊发表科研论文多篇。累计主持并完成国家自然科学基金数项。