Antti Kupiainen (born 23 June 1954, Varkaus, Finland) is a Finnish mathematical physicist.
He was twice an invited speaker at the International Congress of Mathematicians; his ICM talks were in 1990 at Kyoto on Renormalization group and random systems and in 2010 at Hyderabad on Origins of Diffusion.
In the 1980s he developed, with Krzysztof Gawedzki, a renormalization group method (RG) for mathematical analysis of field theories and phase transitions for spin systems on lattices.
[14] With Gawedzki, he established "anomalous inertial range scaling of the structure functions for a model of homogeneous, isotropic advection of a passive scalar by a random vector field."
)[15][16] In 1996 Kupiainen and Bricmont applied high temperature methods from statistical mechanics to chaotic dynamical systems.