CRC Press eBooks

Density matrices

Bruno Juliá Díaz, Arnau Rios Huguet, Héctor Briongos Merino, Javier Rozalén Sarmiento, Artur Polls Martí

Published Sep 17, 2025• 0 citations

Abstract

This chapter delves into the concept of density matrices, a fundamental tool in quantum mechanics for describing the state of a many-body system. Density matrices provide a compact and powerful representation of quantum states, encompassing both pure and mixed states. The study of one-body and two-body density matrices is particularly important for understanding the behavior of many-body systems, especially in contexts like quantum gases, solid-state physics, and quantum chemistry. These matrices encapsulate information about particle distributions and correlations, enabling the derivation of key properties such as energy, momentum, and entropy.

DOI: 10.1201/9781003191339-11

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