John Milnor

For those of a similar name, see John Milner (disambiguation).

John Willard Milnor
Born	February 20, 1931 (1931-02-20) (age 80) Orange, New Jersey
Residence	United States
Nationality	United States
Fields	Mathematics
Institutions	Stony Brook University
Alma mater	Princeton University
Doctoral advisor	Ralph Fox
Doctoral students	Tadatoshi Akiba Jon Folkman John Mather Laurent C. Siebenmann Michael Spivak
Known for	Exotic spheres Fary–Milnor theorem
Notable awards	Putnam Fellow (1949, 1950) Fields Medal (1962) National Medal of Science (1967) Leroy P Steele Prize (1982) Wolf Prize (1989) Abel Prize (2011)

John Willard Milnor (born February 20, 1931) is an American mathematician known for his work in differential topology, K-theory and dynamical systems. He won the Fields Medal in 1962, the Wolf Prize in 1989, and the Abel Prize in 2011.^[1] Milnor is a distinguished professor at Stony Brook University. His wife, Dusa McDuff, is a professor of mathematics at Barnard College.

Life

Milnor was born in Orange, New Jersey. As an undergraduate at Princeton University he was named a Putnam Fellow in 1949 and 1950 and also proved the Fary–Milnor theorem. He continued on to graduate school at Princeton and wrote his thesis, entitled "Isotopy of Links", which concerned link groups (a generalization of the classical knot group) and their associated link structure. His advisor was Ralph Fox. Upon completing his doctorate he went on to work at Princeton.

In 1962 Milnor was awarded the Fields Medal for his work in differential topology. He later went on to win the National Medal of Science (1967), the Leroy P Steele Prize for Seminal Contribution to Research (1982), the Wolf Prize in Mathematics (1989), the Leroy P Steele Prize for Mathematical Exposition (2004), and the Leroy P Steele Prize for Lifetime Achievement (2011). He was an editor of the Annals of Mathematics for a number of years after 1962. He has written a number of books which are remarkable for their easy, clear and precise style.

Milnor was awarded the 2011 Abel Prize, for his "pioneering discoveries in topology, geometry and algebra."^[2] Reacting to the award, Milnor told the New Scientist "It feels very good,", adding that, "One is always surprised by a call at 6 o'clock in the morning."^[3]

His students have included Tadatoshi Akiba, Jon Folkman, John Mather, Laurent C. Siebenmann, and Michael Spivak.

Work

His most celebrated single result is his proof in 1956 of the existence of 7-dimensional spheres with nonstandard differential structure. Later with Michel Kervaire, he showed that the 7-sphere has 15 differentiable structures (28 if one considers orientation). An n-sphere with nonstandard differential structure is called an exotic sphere, a term coined by Milnor. Egbert Brieskorn found simple algebraic equations for 28 complex hypersurfaces in complex 5-space such that their intersection with a small sphere of dimension 9 around a singular point is diffeomorphic to these exotic spheres. Subsequently Milnor worked on the topology of isolated singular points of complex hypersurfaces in general, developing the theory of the Milnor fibration whose fibre has the homotopy type of a bouquet of μ spheres where μ is known as the Milnor number. Milnor's 1968 book on his theory inspired the growth of a huge and rich research area which continues to develop to this day.

In 1961 Milnor disproved the Hauptvermutung by exhibiting two simplicial complexes which are homeomorphic but combinatorially distinct.

Publications

Books

• Milnor, John W. (1963). Morse theory. Annals of Mathematics Studies, No. 51. Notes by M. Spivak and R. Wells. Princeton, NJ: Princeton University Press. ISBN 0-691-08008-9. 
•    (1965). Lectures on the h-cobordism theorem. Notes by L. Siebenmann and J. Sondow. Princeton, NJ: Princeton University Press. ISBN 0-691-07996-X. OCLC 58324. 
•    (1968). Singular points of complex hypersurfaces. Annals of Mathematics Studies, No. 61. Princeton, NJ: Princeton University Press; Tokyo: University of Tokyo Press. ISBN 0-691-08065-8. 
•    (1971). Introduction to algebraic K-theory. Annals of Mathematics Studies, No. 72. Princeton, NJ: Princeton University Press. ISBN 978-0-691-08101-4. 
• Husemoller, Dale; Milnor, John W. (1973). Symmetric bilinear forms. New York, NY: Springer-Verlag. ISBN 978-0-387-06009-5. 
• Milnor, John W.; Stasheff, James D. (1974). Characteristic classes. Annals of Mathematics Studies, No. 76. Princeton, NJ: Princeton University Press; Tokyo: University of Tokyo Press. ISBN 0-691-08122-0. 
• Milnor, John W. (1997) [1965]. Topology from the differentiable viewpoint. Princeton Landmarks in Mathematics. Princeton, NJ: Princeton University Press. ISBN 0-691-04833-9. 
•    (1999). Dynamics in one complex variable. Wiesbaden, Germany: Vieweg. ISBN 3-528-13130-6. 

Journal articles

• Milnor, John W. (1956). "On manifolds homeomorphic to the 7-sphere". Annals of Mathematics (Princeton University Press) 64 (2): 399–405. doi:10.2307/1969983. JSTOR 1969983. MR0082103 
•    (1959). "Sommes de variétés différentiables et structures différentiables des sphères". Bulletin de la Société Mathématique de France (Société Mathématique de France) 87: 439–444. MR0117744. http://www.numdam.org/item?id=BSMF_1959__87__439_0 
•    (1959b). "Differentiable structures on spheres". American Journal of Mathematics (Johns Hopkins University Press) 81 (4): 962–972. doi:10.2307/2372998. JSTOR 2372998. MR0110107 
•    (1961). "Two complexes which are homeomorphic but combinatorially distinct". Annals of Mathematics (Princeton University Press) 74 (2): 575–590. doi:10.2307/1970299. JSTOR 1970299. MR133127 
• Kervaire, Michel A.; Milnor, John W. (1963). "Groups of homotopy spheres: I". Annals of Mathematics (Princeton University Press) 77 (3): 504–537. doi:10.2307/1970128. JSTOR 1970128. MR0148075 
• Milnor, John W. (2011). "Differential topology forty-six years later". Notices of the American Mathematical Society 58 (6): 804–809. http://www.ams.org/notices/201106/rtx110600804p.pdf 

Lecture notes

• Milnor, John Willard; Munkres, James Raymond (2007). "Lectures on Differential Topology". In Milnor, John Willard. Collected papers of John Milnor, Volume 4. American Mathematical Society. pp. 145-176. ISBN 0-8218-4230-7. http://books.google.com/books?id=PrZANUa0dtgC&pg=PA145&lpg=PA145. Retrieved 2011-10-15. 

See also

• Fary–Milnor theorem
• Milnor conjecture in algebraic K-theory
• Milnor conjecture in knot theory
• Milnor conjecture concerning manifolds with nonnegative Ricci curvature
• Milnor fibration
• Milnor map
• Milnor–Thurston kneading theory
• Orbit portrait

References

1. ^ Abelprisen (Abel Prize) website. "The Abel Prize awarded to John Milnor, Stony Brook University, NY". http://www.abelprisen.no/en/. Retrieved March 24, 2011. 
2. ^ Aron, Jacob (March 24, 2011). "Exotic sphere discoverer wins mathematical 'Nobel'". The Hindu. http://www.thehindu.com/sci-tech/science/article1565424.ece. Retrieved 24 March 2011. 
3. ^ Ramachandran, R. (March 23, 2011). "Abel Prize awarded to John Willard Milnor". New Scientist. http://www.newscientist.com/article/dn20281-exotic-sphere-discoverer-wins-mathematical-nobel.html. Retrieved 24 March 2011. 

External links

• O'Connor, John J.; Robertson, Edmund F., "John Milnor", MacTutor History of Mathematics archive, University of St Andrews, http://www-history.mcs.st-andrews.ac.uk/Biographies/Milnor.html .
• John Milnor at the Mathematics Genealogy Project.
• Home page at SUNYSB
• Photo
• Exotic spheres home page

Persondata
Name	Milnor, John Willard
Alternative names
Short description	Mathematician
Date of birth	February 20, 1931
Place of birth	Orange, New Jersey
Date of death
Place of death