Kazuhiro Ichihara (Nara Women's University, JSPS Research Fellow)
Title: Pseudo-Anosov braids on the 2-sphere

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Abstract:
A correspondence between braids on the $2$-disk and those on the $2$-sphere is naturally induced from the inclusion map of the $2$-disk into the $2$-sphere. We consider the problem; which pseudo-Anosov braids on the $2$-disk correspond to not pseudo-Anosov ones on the $2$-sphere.