Seminar: Fundamental Physical Capabilities and Limitations in Communication and Computing

Dr. Lev B. Levitin (Boston University)

Tuesday, March 12, 2013, 11:00 a.m., EV 2.260

Abstract

This talk is a review of fifty years of research focused on revealing the ultimate capabilities of physical systems, on one hand, and their fundamental limitations, on the other, in communication and computing. The following topics are considered.

1. Limits on information transmission by physical agents. Capacity and energy efficiency of photon and corpuscular channels. General bound on minimum energy per information unit.
2. The effect of irreversibility of quantum measurements. Entropy defect and “accessible” information.
3. POVM vs. von Neumann measurements in finite- and infinite-dimensional Hilbert spaces.
4. The maximum speed of computing operations. The Mandelstam-Tamm and Margolus-Levitin bounds. The minimum operation time of quantum gates. The unified tight bound on the rate of computation.
5. Thermodynamic cost of reversible computing. The minimum energy dissipation per computational step.
6. Equivalence relation between information and work. Heat-to-work conversion by use of one-particle and two-particle information.

Bio

Dr. Lev B. Levitin received the M.S. degree in physics from Moscow University, Moscow, USSR, in 1960 and the Ph.D. degree in physical and mathematical sciences from the USSR Academy of Sciences in 1969. Since 1982, he has been with the College of Engineering, Boston University, and since 1986 has been Distinguished Professor of Engineering Science with the Department of Electrical and Computer Engineering at Boston University. He has published over 190 papers, presentations, and patents. His research areas include information theory; quantum communication systems; physics of computation; quantum computing; quantum theory of measurements, mathematical linguistics; theory of complex systems; coding theory; theory of computer hardware testing, reliable computer networks, and bioinformatics. He is a Life Fellow of IEEE, a member of the International Academy of Informatics and other professional societies.