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African Mathematics Seminar
TITLE: The hidden geometry of magnetic skyrmions
SPEAKER: Bernd Schroers, Heriot-Watt University, UK
TIME: 3:00PM Nairobi (GMT+3)
TIME in some well-known cities*:
15:00 (Nairobi, Dar es salaam, Addis Ababa, Kampala, Istanbul, Moscow)
14:00 (Kigali, Cairo, Khartoum, Johannesburg, Maputo, Berlin, Stockholm)
13:00 (Lagos, Rabat, Yaoundé, London))
12:00 (Accra, Dakar)
20:00 (Hong Kong, Shanghai)
21:00 (Tokyo, Seoul)
08:00 (New York)
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Abstract:
This talk is about a model for topological defects in planar ferromagnetic materials, and the geometrical techniques which can be used to obtain infinitely many exact static solutions. The defects, called magnetic skyrmions in this context, are widely studied in physics because of their potential role in future magnetic information storage. The applicability of techniques from complex geometry and gauge theory is surprising, and leads to interesting links with the theory of gravitational lensing. Finally, the dynamics of magnetic skyrmions in response to an applied current, which is of practical interest, also contains unexpected geometry and can be understood in terms of quaternionic Moebius transformations.