Luigi Chierchia (born 1957) is an Italian mathematician, specializing in nonlinear differential equations, mathematical physics, and dynamical systems (celestial mechanics and Hamiltonian systems).[1]
Chierchia studied physics and mathematics at the Sapienza University of Rome with Laurea degree in 1981 with supervisor Giovanni Gallavotti.[2] After a year of military service, Chierchia studied mathematics at the Courant Institute of New York University and received his PhD there in 1985.[1] His doctoral dissertation Quasi-Periodic Schrödinger Operators in One Dimension, Absolutely Continuous Spectra, Bloch Waves and integrable Hamiltonian Systems was supervised by Henry P. McKean.[3] As a postdoc, Chierchia studied at the University of Arizona, ETH Zurich and the École Polytechnique in Paris. Since 2002 he has been Professor of Mathematical Analysis at Roma Tre University.[1]
With Fabio Pusateri and his doctoral student Gabriella Pinzari, he succeeded in extending the KAM theorem for the three-body problem to the n-body problem.[4] In KAM theory, Chierchia addressed invariant tori in phase-space Hamiltonian systems and stability questions. He has also done research on Arnold diffusion, spectral theory of the quasiperiodic one-dimensional Schrödinger equation, and analogs of KAM theory in infinite-dimensional Hamiltonian systems and partial differential equations (almost periodic nonlinear wave equations).
He was an invited speaker (with Gabriella Pinzari) at the International Congress of Mathematicians in Seoul in 2014,[5] and at the conference Dynamics, Equations and Applications in Kraków in 2019.[6]