Claude LeBrun | |
|---|---|
 LeBrun in 2012 | |
| Citizenship | United States |
| Alma mater | Rice University University of Oxford |
| Known for | LeBrun manifolds LeBrun-Salamon Conjecture |
| Scientific career | |
| Fields | Mathematics |
| Institutions | Stony Brook University |
| Doctoral advisor | Roger Penrose |
| Doctoral students | Christina Tønnesen-Friedman |
Claude R. LeBrun (born 1956) is an American mathematician who holds the position of Distinguished Professor of Mathematics atStony Brook University. Much of his research concerns theRiemannian geometry of 4-manifolds, or related topics in complex and differential geometry.
After enrolling as an undergraduate atRice University at age 16, LeBrun received hisMaster of Arts in mathematics fromRice in 1977. He then went on to earn hisD.Phil. (Oxford equivalent of a Ph.D.) from theUniversity of Oxford in 1980, for a thesis on complex differential geometry written under the supervision ofRoger Penrose.[1] That same year, he then accepted his first faculty position at Stony Brook.[2] Although he would eventually go on to spend most of his career at Stony Brook, he has also held positions at a number of other institutions, including theInstitut des Hautes Études Scientifiques, theMathematical Sciences Research Institute, and theInstitute for Advanced Study.[3]
He is the namesake of theLeBrun manifolds, a family of self-dual manifolds that he discovered in 1989 and that was named after him byMichael Atiyah andEdward Witten.[4] LeBrun is also known for his work onEinstein manifolds and theYamabe invariant. In particular, he produced examples showing that theconverse of theHitchin–Thorpe inequality does not hold: there exist infinitely many four-dimensional compact smooth simply connectedmanifolds that obey the inequality but do not admit Einstein metrics.
LeBrun was an invited speaker at the 1994International Congress of Mathematicians.[2] In 2012, he became a Fellow of theAmerican Mathematical Society.[5] In 2016, a conference in his honor was held in Montreal.[6]In 2018, he first became a Simons Foundation Fellow in Mathematics.[7]In 2020, he was appointed as Distinguished Professor at the State University of New York.[8] In 2025, he became a Simons Foundation Fellow for the second time,[9] while also becoming a laureate of the Chaires d'Excellence program of the Fondation Sciences Mathématiques de Paris.[10]
