100, rue des maths 38610 Gières / GPS : 45.193055, 5.772076 / Directeur : Louis Funar

Sumio Yamada

Gravitational solitons and instantons to the Einstein equation
Jeudi, 30 Novembre, 2023 - 14:00
Résumé : 

The Einstein equation with time symmetry has been regarded as an elliptic variational problem, ever since H. Weyl in 1916 described the Schwarzschild metric using a single harmonic function. In a series of collaborative work with Marcus Khuri, Martin Reiris and Gilbert Weinstein, we constructed 5-dimensional gravitational solitons, and consequently 4-dimensional gravitational (Riemannian) instantons.  In 3+1 spacetime dimensions, there are known to be no nontrivial solitons (Lichnerowicz), and our new construction seems to indicate that the geometry of  higher dimensional Einstein spacetimes is geometrically more fertile.

Institution de l'orateur : 
Gakushuin University
Thème de recherche : 
Théorie spectrale et géométrie
Salle : 
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