Dr. Shinsei Ryu

Award Citation

For uncovering profound connections between quantum information and gravitational geometry and for establishing a foundation for the systematic classification of topological phases of matter

Biography

Education

• The University of Tokyo　Ph.D. Applied Physics, 2005
• The University of Tokyo　M.S. Applied Physics, 2002
• The University of Tokyo　B.S. Physics, 2000

Professional Appointments

• Professor of Physics, Princeton University (2020–present)
• Visiting Scientist, RIKEN, Japan (2016–present)
• Professor of Physics, University of Chicago (2019–2020)
• Associate Professor of Physics, University of Chicago (2017–2019)
• Associate Professor of Physics, University of Illinois at Urbana-Champaign (2016–2017)
• Assistant Professor of Physics, University of Illinois at Urbana-Champaign (2011–2016)

Awards

• Dirac Medal of the ICTP, 2024
• Simons Investigator Award, 2018
• Nishina Memorial Prize（仁科記念賞）, 2015
• New Horizons in Physics Prize, 2014
• Nishinomiya-Yukawa Memorial Prize（西宮湯川記念賞）, 2013

and many others

Research Summary

Quantum entanglement refers to a phenomenon in which the quantum states of subatomic particles are interconnected in that they cannot be described independently of one another even if they are separated in space by an arbitrary distance. In 2006, Dr. Ryu and Tadashi Takayanagi (now Professor at the Yukawa Institute for Theoretical Physics, Kyoto University) demonstrated that the magnitude of entanglement calculated in field theory coincides with the area of a minimal surface in gravitational theory. This relationship is known as the Ryu-Takayanagi formula. Their work raised the foundational question of whether spacetime geometry itself might emerge from quantum entanglement. Thus, it has fundamentally transformed the trajectory of research on quantum gravity by sparking this new line of exploration.
Furthermore, between 2008 and 2010, in collaboration with Andreas Schnyder (now Group Leader at Max Planck Institute), Akira Furusaki (now Group Director at RIKEN), and Andreas Ludwig (Professor at the University of California), Dr. Ryu demonstrated that topological insulators and superconductors can be systematically categorized into ten symmetry classes based on their symmetry and dimensionality. This classification scheme is widely known as the “topological periodic table,” and it has been widely adopted as a theoretical blueprint to predict previously undiscovered phases of matter.

Notes:
Ryu-Takayanagi formula: This formula posits a formula that relates the magnitude of quantum　entanglement (i.e., entanglement entropy) to the area of a minimal surface in gravitational theory.
Topological Periodic Table: This classification categorizes topological insulators and superconductors into ten distinct symmetry classes according to their symmetry and spatial dimensionality.

Selection Highlights

• Originality: Dr. Ryu’s work bridges the conventionally distinct domains of quantum information and gravitation through a single mathematically elegant formula.
• Paradigm Shift: These insights have defined new directions in modern research on quantum gravity by presenting the foundational hypothesis that spacetime geometry emerges from quantum entanglement.
• Systematic Framework: Dr. Ryu’s work has also established a comprehensive taxonomy of states of matter that classifies topological insulators and superconductors into ten symmetry classes based on their symmetry and dimensionality.
• Predictive Power: The topological periodic table continues to guide the exploration and synthesis of topological materials today because it provides a theoretical framework that can be applied to predict previously undiscovered phases.