Open Lecture — Why are Many-Body Problems in Physics so Difficult? A Quantum Information Perspective

Determining the physical behavior of systems composed of several particles is, in general, very hard. The reason is that the number of possible combinations of states increases exponentially with the number of particles. For quantum systems the situation is even worse, since it is even very hard to specify the states in thermal equilibrium. This is due to the presence of a very intriguing property, called entanglement. In this talk I will explain this phenomenon in detail and will review several approaches to assessing this difficulty and to overcoming it under certain conditions. Some of the ideas for achieving this goal come from the field of quantum information, where experience with building powerful (so-called) quantum computers can shed new light on some of these classical and quantum problems.

Light refreshments will be served before the lecture at 3 p.m.