Talks

Can you hear the degree of a map from the circle into itself? New ideas about the degree and the Jacobian of maps from S^n into itself

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Haïm Brezis 
2009-07-02 
14:00 - 15:00 
101 , Mathematics Research Center Building (ori. New Math. Bldg.)

A few years ago -- following a suggestion by I. M. Gelfand-- I discovered an intriguing connection between the topological degree of a map from the circle into itself and its Fourier coefficients. This relation is easily justified when the map is smooth. However, the situation turns out to be much more delicate if one assumes only continuity, or even Holder continuity.