Bosonization and Quantum Hydrodynamics

TL;DR

This paper develops a bosonization method using hydrodynamic variables applicable in any dimension, providing a unified framework for analyzing fermionic systems and their correlations, including a study of 2D Fermi systems with interactions.

Contribution

It introduces a dimension-independent bosonization formalism based on hydrodynamic variables, connecting to known 1D results and extending to higher dimensions with new correlation formulas.

Findings

Equivalent to Tomonaga-Luttinger in 1D

Derived a general density correlation generating function

Analyzed metal-insulator transition in 2D Fermi systems

Abstract

It is shown that it is possible to bosonize fermions in any number of dimensions using the hydrodynamic variables, namely the velocity potential and density. The slow part of the Fermi field is defined irrespective of dimensionality and the commutators of this field with currents and densities are exponentiated using the velocity potential as conjugate to the density. An action in terms of these canonical bosonic variables is proposed that reproduces the correct current and density correlations. This formalism in one dimension is shown to be equivalent to the Tomonaga-Luttinger approach as it leads to the same propagator and exponents. We compute the one-particle properties of a spinless homogeneous Fermi system in two spatial dimensions with long-range gauge interactions and highlight the metal-insulator transition in the system. A general formula for the generating function of density correlations is derived that is valid beyond the random phase approximation. Finally, we write down a formula for the annihilation operator in momentum space directly in terms of number conserving products of Fermi fields.