The notion of chaos is frequently invoked in the foundations of quantum statistical physics. Yet, the definition of quantum chaos for many-particle systems is still not fully understood. It is widely believed that classical chaotic properties are recovered, when one deals with quantum systems in the macroscopic limit and on physically relevant time scales. We show, however, that, even in the macroscopic limit and on physically relevant timescales, generic systems of interacting quantum spins do not exhibit the basic property of classical chaotic systems, namely, exponential sensitivity to small perturbations. This result is obtained by comparing the responses of classical and quantum spin systems to imperfect reversal of spin dynamics known as Loschmidt echo. The above absence of exponential sensitivity to small perturbations is an encouraging news for the efforts to create quantum simulators. It is also predicted to have measurable consequences for nuclear magnetic resonance experiments.
SPEAKER INTRODUCTION:
Dr. Boris Fine is a theoretical physicist specializing in the field of Condensed Matter Physics. His research interests include solid-state nuclear magnetic resonance, high-temperatures superconductivity, and a broader set of topics associated with the foundations of quantum statistical physics and the role of chaos in many-particle systems. He graduated from Moscow Institute of Physics and Technology in 1994. In 2000, he obtained his Ph.D. degree from the University of Illinois at Urbana-Champaign. His Ph.D. advisor was Prof. A. J. Leggett. Boris Fine’s subsequent career included postdoctoral positions at Utrecht University, Max Planck Institute for the Physics of Complex Systems in Dresden, and University of Tennessee-Knoxville/Oak Ridge National Laboratory. In 2008, he became the leader of Young Investigators Group “Quantum Dynamics and Complex Quantum Systems” at the University of Heidelberg. Since August of 2013, Boris Fine works as a professor at Nazarbayev University. He is also a guest professor at the University of Heidelberg.
When: October 17, 2013 13.00 – 14.30
Where: Skolkovo School of management, Beijing – 1 Auditorium
