# セミナー

## 非線形解析セミナー

タイトル A justification of the definition of curvature in Regge Calculus 2018年7月11日 16:00 ～ 17:00 Professor Snorre Christiansen (University of Oslo) 慶應義塾大学理工学部 14棟 631A/B (創想館 6階 ミーティング1A/1B) Regge calculus was introduced in 1961 as a coordinate free and discrete analogue of Einstein's theory of gravitation. Yet, in spite of its beautiful geometric features, the bulk of numerical computations in general relativity is, as of today, carried out by other methods, probably because of a lack of understanding of its stability and convergence properties. Surprisingly, Regge defined a curvature of simplicial manifolds, equipped with a piecewise constant metric, with a partial continuity requirement between simplices. I will provide a justification of this definition by a smoothing procedure: the curvature of the smoothened metrics converges to the curvature defined combinatorially by Regge, in the sense of measures, as the smoothing parameter goes to zero.