An Introduction to Quantum Order, String-net Condensation, and Emergence of Light and Fermions

TL;DR

This paper reviews recent developments in quantum states of matter characterized by quantum order, highlighting how string-net condensation leads to emergent gauge bosons and fermions from purely bosonic systems.

Contribution

It introduces the concept of quantum order and demonstrates its connection to string-net condensation, explaining the emergence of light and fermions in bosonic models.

Findings

Quantum order extends traditional symmetry-breaking descriptions.

String-net condensation explains the emergence of gauge bosons and fermions.

Pure bosonic models can give rise to light and fermions through quantum order.

Abstract

We review some recent work on new states of matter. Those states cannot be described symmetry breaking and hence contain a new kind of order -- quantum order. Some quantum orders are shown to be closely related to string-net condensations. Those quantum orders lead to an emergence of gauge bosons and fermions from pure bosonic models.