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October 28, 2025 By GeometryAdmin

Siqi He to talk in geometry seminar 03/11/25

Siqi He (Chinese Academy of Sciences) will give the geometry seminar at 2pm on 3rd November, in the Salle des Profs (9th floor building NO). Siqi’s title is “On some properties of Z2 eigenvalues on round two sphere” and his abstract is below.

In this talk, we will introduce an eigenvalue problem for the Laplace operator on multivalued functions, defined on the complement of the 2n points on the round two sphere, introduced and systematically studied by Taubes-Wu. These eigenvalues could also be viewed as functions on the configuration spaces of points, where the critical points, which serve as local singularity models for gauge theoretical problems, are of particular interest. We will discuss several existence and rigidity results towards these critical points. This is a joint work with J.Chen.

Filed Under: geometry seminar news

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Address

Département de mathématiques
Université libre de Bruxelles CP 218
Boulevard du Triomphe, Bruxelles 1050,
Belgium

Getting here

The department of mathematics is in building NO, on the Campus de la Plaine, of the Université libre de Bruxelles. The geometry group is on the 7th floor. This page has a map of the campus as well as information on how to reach it via public transport. See the STIB website for more information on public transport in Brussels.

Image credits

Polished ammonite fossil, by Kara Stenberg, Creative Commons licence CC BY-NC 2.0.

Model of 3D projection of a 120-cell, by Edmund Harriss.

The root system of the exceptional Lie algebra E8. By Jared Tarbell, Creative Commons Licence CC BY 2.0.

Getting here

The department of mathematics is in building NO, on the Campus de la Plaine, of the Université libre de Bruxelles. The geometry group is on the 7th floor. This map shows NO, as well as the metro station Delta and entrance 2, which is right by the stop for the number 71 and 72 buses. The number 95 also stops a short walk from the department. See the STIB website for more information on public transport in Brussels.

Image credits

Polished ammonite fossil, by Kara Stenberg, Creative Commons licence CC BY-NC 2.0.

Model of 3D projection of a 120-cell, by Edmund Harriss.

The root system of the exceptional Lie algebra E8. By Jared Tarbell, Creative Commons Licence CC BY 2.0.

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