for this workshop

## Fisher-Hartwig asymptotics, Szego expansions, and applications to statistical physics

at the

American Institute of Mathematics, San Jose, California

organized by

Hajo Leschke, Alexander V. Sobolev, and Wolfgang Spitzer

This workshop, sponsored by AIM and the NSF, will focus on the theory of Toeplitz matrices (TM) and Wiener-Hopf operators (WHO).

In the recent ten or so years, the theory of these operators (TM and WHO) attracted a great deal of renewed attention from mathematical and theoretical physics communities due to the mathematical beauty of problems involved, and due to new applications in physics. For example, novel developments in quantum information theory and statistical physics concern the asymptotics of the (quantum) entanglement entropy of thermal equilibrium states, the overlap of ground states in the Anderson orthogonality catastrophe and the emptiness formation probability in quantum spin models. These quantities can be deduced from suitable Szego limit theorems, that is, from asymptotic results for traces of certain functions of TM and WHO.

The workshop will focus on the following problems.

- Double scaling limits for TM and WHO with symbols which, apart from the scaling parameter $L$, depend on another parameter, say on temperature $T$, as $L \rightarrow \infty$ and $T \downarrow 0$ in a coordinated way.
- Asymptotics for block TM and WHO with Fisher-Hartwig singularities.
- The study of multi-term asymptotics for TM and WHO with the aim to detect topological entropy, that is, a term depending, for instance, on the Euler characteristics of the spatial domain.
- Extension to TM and WHO which are translation invariant with respect to a group different from (all) Euclidean translations. Examples include periodic potentials, magnetic fields and random operators.

The workshop will differ from typical conferences in some regards. Participants will be invited to suggest open problems and questions before the workshop begins, and these will be posted on the workshop website. These include specific problems on which there is hope of making some progress during the workshop, as well as more ambitious problems which may influence the future activity of the field. Lectures at the workshop will be focused on familiarizing the participants with the background material leading up to specific problems, and the schedule will include discussion and parallel working sessions.

The deadline to apply for support to participate in this workshop has passed.

For more information email *workshops@aimath.org*