Quantum matters: Physics beyond Landau's paradigms

TL;DR

This paper reviews recent theoretical advances in quantum many-particle physics that challenge Landau's traditional concepts of quasiparticles and order parameters, highlighting physics beyond established paradigms.

Contribution

It offers an overview of new theoretical frameworks and ideas that extend beyond Landau's paradigms in quantum many-body physics.

Findings

Experiments question the universality of quasiparticles and order parameters.

Theoretical work confirms physics beyond Landau's paradigms.

New models describe exotic quantum states.

Abstract

Central to our understanding of quantum many particle physics are two ideas due to Landau. The first is the notion of the electron as a well-defined quasiparticle excitation in the many body state. The second is that of the order parameter to distinguish different states of matter. Experiments in a number of correlated materials raise serious suspicions about the general validity of either notion. A growing body of theoretical work has confirmed these suspicions, and explored physics beyond Landau's paradigms. This article provides an overview of some of these theoretical developments.