2019.11.16 (SAT) − 24 (SUN) 11AM−7PM ※最終日は5PM迄

一般 ¥1,000 / 学生 ¥500

kudan house(東京・九段下)

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2019.11.16 (SAT) − 24 (SUN) 11AM−7PM Open until 5PM on the last day

Adults ¥1,000 / Student ¥500

kudan house

View Google Maps


Two ways of visualization of three-dimensional sphere surface in the Four-Dimensional Euclidean Space.
Sphere, a geometrical shape is too symmetric, flat and not eye-catching. Sphere in four dimensional space is even more difficult to imagine. In contrast with its simplicity in the mathematical description , the complicity of its visualization is not only purely impressive, but also suggestion of where the beauty comes from.
Seeing it in Hyper spherical coordinate system is a kind of analogy of 2-dimensional sphere surface in three-dimensional space. On the other hand, the formula in Hopf Coordinates System is more symmetric and looks like non-human way. More surprisingly, that is also invented by a man, Heinz Hopf.

Norimichi Hirakawa



Born in 1982, Norimichi Hirakawa’s interest lies in the most primitive of technologies, calculation. He began creating art works since 2005 which is focused on installations that use either mathematical processing itself as conducted through computer programming or the results of that processing. He started a new project through a residency at The Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) in 2016 and at the ALMA telescope, located at Chile’s highest point of approximately 5000 meters in 2017. based in Sapporo since 2019.