Bernard Morin

Looping animated cutaway view of Boy's surface.

Bernard Morin (French: [mɔʁɛ̃]; born 1931) is a French mathematician, specifically a topologist, who is now retired. He has been blind since age 6 due to glaucoma, but his blindness did not prevent him from having a successful career in mathematics.

Morin was a member of the group that first exhibited an eversion of the sphere, i.e. a homotopy (topological metamorphosis) which starts with a sphere and ends with the same sphere but turned inside-out. He also discovered the Morin surface, which is a half-way model for the sphere eversion, and used it to prove a lower bound on the number of steps needed to turn a sphere inside out.

He discovered the first parametrization of Boy's surface (earlier used as a half-way model) in 1978. His graduate student François Apéry later discovered (in 1986) another parametrization of Boy's surface, which conforms to the general method for parametrizing non-orientable surfaces.^[1]

Morin worked at the Institute for Advanced Study in Princeton. Most of his career, though, he spent at the University of Strasbourg.

Morin's surface.

Notes

1. Weisstein, Eric W. "Boy Surface." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/BoySurface.html

References

• George K. Francis & Bernard Morin (1980) "Arnold Shapiro’s Eversion of the Sphere", Mathematical Intelligencer 2(4):200–3.

External links

• Photos of Morin with stereolithography models of sphere eversion.
• The World of Blind Mathematicians, PDF file at the American Mathematical Society's website.