John Cardy facts for kids

John Lawrence Cardy, born on March 19, 1947, in England, is a brilliant British-American theoretical physicist. He is famous for his work in understanding how materials behave at a very tiny level. He also studies how systems change and interact, especially focusing on something called critical phenomena and two-dimensional conformal field theory.

Professor Cardy studied at Downing College, Cambridge, before moving to the University of California, Santa Barbara, in 1977. Later, in 1993, he joined the University of Oxford. There, he was a Professor of Physics until 2014. He also spent time as a researcher at the University of California, Berkeley, from 2015 to 2023.

Understanding John Cardy's Research

John Cardy's early research, before 1978, was in particle physics. This field looks at the smallest particles that make up everything. He studied how these tiny particles scatter or bounce off each other at high energies.

Exploring Condensed Matter Physics

After 1978, Professor Cardy started applying new ideas to condensed matter physics. This area of physics studies the properties of materials, like solids and liquids. He used methods from quantum field theory and the renormalization group. These are complex tools that help scientists understand how materials behave, especially during big changes.

Critical Phenomena and Conformal Invariance

He focused on critical phenomena. This is when a material undergoes a sudden, dramatic change, like water turning into ice. In the 1980s, he helped create the theory of conformal invariance. This idea explains how certain physical systems look the same even when stretched or squashed in specific ways. These ideas were also important in other areas, like string theory and the physics of black holes.

Contributions to Probability and Quantum Systems

In the 1990s, Professor Cardy used conformal invariance to solve many problems in percolation theory. This is a part of mathematics that studies how things connect or spread through a network. His work inspired mathematicians who later won major awards, like the Fields Medal. More recently, he has explored quantum entanglement. This is a strange phenomenon where two particles are linked, no matter how far apart they are. He also studied how many-body systems behave when they are not in a balanced state.

Awards and Recognition

John Cardy has received many important awards for his groundbreaking work. In 1991, he was chosen as a Fellow of the Royal Society, a very prestigious scientific group. He received the Dirac Medal from the Institute of Physics in 2000. The American Physical Society gave him the Lars Onsager Prize in 2004. In 2010, he was awarded the Boltzmann Medal. He also received the Dirac Medal from the International Centre for Theoretical Physics in 2011. Most recently, in 2024, he won the Breakthrough Prize in Fundamental Physics.

Formulas Named After Him

Professor Cardy is especially known for his contributions to conformal field theory. Several important concepts and formulas in physics are named after him. These include the Cardy formula for black hole entropy, the Cardy formula in percolation theory, and the Cardy conditions in boundary conformal field theory. These formulas help scientists understand complex physical systems.

Selected Works

• Scaling and renormalization in statistical physics. Cambridge University Press, 1996
• with Krzysztof Gawędzki, Gregory Falkovich: Non equilibrium statistical mechanics and turbulence. London Mathematical Society Lecture notes, Cambridge University Press, 2008
• Conformal Invariance and Statistical Mechanics. in Les Houches Lectures, vol. 49, 1988
• as editor: Finite Size Scaling. Elsevier 1988
• Cardy Conformal Invariance in Percolation, Self-Avoiding Walks and Related Problems, 2002
• Cardy Conformal field theory and statistical mechanics, Les Houches Lectures 2008
• Cardy, Pasquale Calabrese Entanglement entropy and conformal field theory, J. Phys. A, 42, 2009
• Cardy Entanglement entropy in extended quantum systems, 2007

External links

• John Cardy's homepage