Nancy Hingston | |
---|---|
Nationality | American |
Alma mater | Harvard University |
Known for | Generic existence of infinitely many closed geodesics Proof of the Conley conjecture |
Scientific career | |
Fields | Mathematics |
Doctoral advisor | Raoul Bott |
Nancy Burgess Hingston is a mathematician working in algebraic topology and differential geometry. She is a professor emerita of mathematics at The College of New Jersey. [1]
Nancy Hingston's father William Hingston was superintendent of the Central Bucks School District in Pennsylvania; her mother was a high school mathematics and computer science teacher. [2] She graduated from the University of Pennsylvania with a double major in mathematics and physics. After a year studying physics as a graduate student, she switched to mathematics, [1] and completed her PhD in 1981 from Harvard University under the supervision of Raoul Bott. [3]
Before joining TCNJ, she taught at the University of Pennsylvania. [2] She has also been a frequent visitor to the Institute for Advanced Study, [1] and has been involved with the Program for Women and Mathematics at the Institute for Advanced Study since its founding in 1994. [4]
Nancy Hingston made major contributions in Riemannian geometry and Hamiltonian dynamics, and more specifically in the study of closed geodesics and, more generally, periodic orbits of Hamiltonian systems. In her very first paper, [5] she proved that a generic Riemannian metric on a closed manifold possesses infinitely many closed geodesics. In the 1990s, she proved that the growth rate of closed geodesics in Riemannian 2-spheres is at least the one of prime numbers. [6] In the years 2000s, she proved the long-standing Conley conjecture from symplectic geometry: every Hamiltonian diffeomorphism of a standard symplectic torus of any even dimension possesses infinitely many periodic points [7] (the result was subsequently extended by Viktor Ginzburg to more general symplectic manifolds).
Nancy Hingston was an invited speaker at the International Congress of Mathematicians in 2014. [8] [9] [10]
She is a fellow of the American Mathematical Society, for "contributions to differential geometry and the study of closed geodesics." [11]
Her husband, Jovi Tenev, is a lawyer. [2] She has three children. [9]
Differential geometry is a mathematical discipline that studies the geometry of smooth shapes and smooth spaces, otherwise known as smooth manifolds. It uses the techniques of differential calculus, integral calculus, linear algebra and multilinear algebra. The field has its origins in the study of spherical geometry as far back as antiquity. It also relates to astronomy, the geodesy of the Earth, and later the study of hyperbolic geometry by Lobachevsky. The simplest examples of smooth spaces are the plane and space curves and surfaces in the three-dimensional Euclidean space, and the study of these shapes formed the basis for development of modern differential geometry during the 18th and 19th centuries.
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In mathematics, a symplectomorphism or symplectic map is an isomorphism in the category of symplectic manifolds. In classical mechanics, a symplectomorphism represents a transformation of phase space that is volume-preserving and preserves the symplectic structure of phase space, and is called a canonical transformation.
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In the mathematical field of differential geometry, Ricci-flatness is a condition on the curvature of a Riemannian manifold. Ricci-flat manifolds are a special kind of Einstein manifold. In theoretical physics, Ricci-flat Lorentzian manifolds are of fundamental interest, as they are the solutions of Einstein's field equations in a vacuum with vanishing cosmological constant.
Hopf–Rinow theorem is a set of statements about the geodesic completeness of Riemannian manifolds. It is named after Heinz Hopf and his student Willi Rinow, who published it in 1931. Stefan Cohn-Vossen extended part of the Hopf–Rinow theorem to the context of certain types of metric spaces.
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In mathematics, Floer homology is a tool for studying symplectic geometry and low-dimensional topology. Floer homology is a novel invariant that arises as an infinite-dimensional analogue of finite-dimensional Morse homology. Andreas Floer introduced the first version of Floer homology, now called symplectic Floer homology, in his proof of the Arnold conjecture in symplectic geometry. Floer also developed a closely related theory for Lagrangian submanifolds of a symplectic manifold. A third construction, also due to Floer, associates homology groups to closed three-dimensional manifolds using the Yang–Mills functional. These constructions and their descendants play a fundamental role in current investigations into the topology of symplectic and contact manifolds as well as (smooth) three- and four-dimensional manifolds.
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Helmut Hermann W. Hofer is a German-American mathematician, one of the founders of the area of symplectic topology.
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The Conley conjecture, named after mathematician Charles Conley, is a mathematical conjecture in the field of symplectic geometry, a branch of differential geometry.