Many-body techniques are computational and theoretical methods used to describe and solve quantum or classical systems with a large number of interacting particles, where correlations invalidate simple mean-field or single-particle approximations. They encompass approaches such as Green’s function methods, diagrammatic perturbation theory, coupled-cluster theory, configuration interaction, quantum Monte Carlo, density-matrix renormalization group, and dynamical mean-field theory. These techniques systematically incorporate many-body correlations into observables like excitation spectra, ground-state energies, and response functions, and are central in condensed matter physics, nuclear structure, quantum chemistry, and strongly correlated materials research.
Physicists have used a machine-learning method to identify surprising new twists on the non-reciprocal forces governing a many-body system.
General Physics
Aug 1, 2025
2
299
A research team led by TU Darmstadt has transformed a difficult problem in quantum physics into a much simpler version through innovative reformulation—without losing any important information. The scientists have thus developed ...
Quantum Physics
Jul 24, 2025
0
67
Caltech scientists have found a fast and efficient way to add up large numbers of Feynman diagrams, the simple drawings physicists use to represent particle interactions. The new method has already enabled the researchers ...
General Physics
Jul 10, 2025
0
167
Hollow atoms are special atoms with multiple missing electrons in their inner shells, while their outer shells are still fully or partially filled with electrons. Studying the production mechanisms, internal structure, and ...
General Physics
Jul 9, 2025
0
41
From subatomic particles to complex molecules, quantum systems hold the key to understanding how the universe works. But there's a catch: when you try to model these systems, that complexity quickly spirals out of control—just ...
Quantum Physics
Oct 17, 2024
0
193
By cleverly applying a computational technique, scientists have made a breakthrough in understanding the "pseudogap," a long-standing puzzle in quantum physics with close ties to superconductivity. The discovery, presented ...
Superconductivity
Sep 19, 2024
0
231
The fusion of two nuclei is a complex process influenced by many factors. These factors include not only the relative energy and angular momentum of the two nuclei, but also how their structures evolve as they collide. The ...
General Physics
Jul 15, 2024
1
337
Tensor force is a crucial ingredient of the nucleon-nucleon (NN) interaction, and has an important impact on the structural and dynamical properties of the nuclear many-body system. Many efforts have been devoted to studying ...
General Physics
Jul 9, 2024
0
81
When atomic nuclei and subatomic particles interact, the results are incredibly complex. These are the "many body problems" of quantum mechanics. To help make sense of these interactions, scientists create ways to simplify ...
General Physics
Jul 8, 2024
0
71
Since the first successful fabrication of a two-dimensional structure of carbon atoms about 20 years ago, graphene has fascinated scientists. A few years ago, researchers discovered that two layers of graphene, slightly twisted ...
Nanomaterials
Apr 27, 2022
0
126
