New preprint: Hölder continuity of solutions to quasilinear hypoelliptic equations (w/ C. Imbert)

DOWNLOAD THE PDF FROM ARXIV

We prove that L^2 weak solutions to a quasilinear hypoelliptic equations with bounded measurable coefficients are Hölder continuous. The proof relies on classical techniques developed by De Giorgi and Moser together with the averaging lemma developped in kinetic theory. The latter tool is used in the proof of the local gain of integrability of sub-solutions and in the proof of an “hypoelliptic isoperimetric De Giorgi lemma”, obtained by combining the classical isoperimetric inequality on the diffusive variable with the structure of the integral curves of the first-order part of the operator.

Birth of a Theorem… Villani on the BBC

Birth of a TheoremCédric Villani was on BBC 2 on the occasion of the publication of the book “Birth of a Theorem” (translation of his book “Théorème vivant” describing the making of our theorem).
Here is the link (Villani starts at 37:45):
http://www.bbc.co.uk/iplayer/episode/b055v6pf/newsnight-11032015
Also, BBC RADIO 4 has a series of programs with Cedric Villani this week:
1. The Mathematical Mind with Cedric Villani: http://www.bbc.co.uk/programmes/b054pj6y
2. Book of the week (Birth of a Theorem by Cedric Villani):
Episode 1: http://www.bbc.co.uk/programmes/b054pmgr
Episode 2: http://www.bbc.co.uk/programmes/b054qc1m
Episode 3: http://www.bbc.co.uk/programmes/b054qd81
Episode 4: http://www.bbc.co.uk/programmes/b054t3s4
Episode 5: http://www.bbc.co.uk/programmes/b054tl6z