# Albert J. Libchaber

Wolf Prize Laureate in Physics 1986

**Albert J. Libchaber**

#### Affiliation at the time of the award:

**University of Chicago, USA**

#### Award citation:

**“for his brilliant experimental demonstration of the transition to turbulence and chaos in dynamical systems”.**

#### Prize share:

**Albert J. Libchaber**

**Mitchell J. Feigenbaum **

Mitchell J. Feigenbaum and Albert J. Libchaber together have opened up an entirely new field of research.

Professor Albert J. Libchaber is one of the leading figures in experimental condensed matter physics. He has made the first experimental observation of the bifurcation cascade that leads to chaos and turbulence in convective Rayleigh-Benard systems. Considering the complexity of all past work on turbulence, Libchaber’s experiments are astounding in their simplicity and elegance. Using microbolometers (scale 1ч) engraved in the convective cell he was able to observe temperature fluctuations without perturbing the environment. In that way, he clearly observed the bifurcations that lead to chaos: period doubling, possibly accompanied by locking of several incommensurate frequencies. The theoretical predictions of Feigenbaum are thus entirely confirmed. His first work was done on 4He; he has been using mercury, in which an applied magnetic field provides an additional degree of freedom. The experiment is so perfect that it can measure quantitatively the Feigenbaum critical exponents that characterize the cascade to chaos.