Wolf Prize Laureate in Physics 2021
Affiliation at the time of the award:
University of Rome ‘‘La Sapienza’’, Italy
“for ground-breaking discoveries in disordered systems, particle physics and statistical physics”.
Giorgio Parisi, Professor of theoretical physics at the University of Rome, ‘‘La Sapienza’’, whose research has focused on quantum field theory, statistical mechanics, and complex systems.
His father and grandfather were both construction workers, and the young Parisi was encouraged to become an engineer. Instead, Parisi was drawn to the complicated abstractions he read in books of popular science, science fiction and mathematics and wanted to do something that involved research. Parisi was torn between majoring in physics and mathematics. He attracted by the adventurous nature of research and sees physics as the terrain on which to play his intellectual challenge at the highest level. Parisi graduated in physics in 1970 in the shortest possible time, under the direction of Nicola Cabibbo. Parisi’s achievements span many areas of modern physics and even the field of biological models. He is author of many books, articles and ideas that have opened up new areas of research.
The Wolf Prize in Physics is awarded to Giorgio Parisi for being one of the most creative and influential theoretical physicists in recent decades. His work has a large impact on diverse branches of physical sciences, spanning the areas of particle physics, critical phenomena, disordered systems as well as optimization theory and mathematical physics. In 1977 together with Altarelli, Parisi discovered the evolution equations allowing to accurately formulating how quarks and gluons are distributed inside the proton and nuclei (they were discovered independently by Yu. L. Dokshitzer). Parisi’s work was indispensable in analyzing the fundamental structure of matter at the smallest possible distance scale done through high-energy scattering of elementary particles. His results have served in preparing and analyzing the experiments performed at the Large-Hardon-Collider (LHC), for dark matter searches, and are used today in the planning experiments for the Future Circular Collider.
In another series of seminal works from 1979-84, Parisi introduced the concept of replica symmetry breaking and applied it to models of “spin-glasses” (the Sherrington-Kirkpatrick model), where no simple order parameter exists. His remarkable intuition led him to the discovery of the non-ergodic nature of the frustrated spin-glass phase, where many pure states unrelated by symmetry coexist, with a highly non-trivial ultra-metric structure. Parisi’s suggestion of a new organization of matter has led to a paradigm shift in statistical physics, and many applications followed in other disordered systems such as structural glasses, neural networks, and combinatorial optimization theory.
His highly innovative work (with Sourlas) in studying classical phase transitions has led to the possibility to identify the actual realization of a symmetry called supersymmetry in condensed matter systems.