scholarly journals Low-energy effective theories of the two-thirds filled Hubbard model on the triangular necklace lattice

2014 ◽  
Vol 90 (3) ◽  
Author(s):  
C. Janani ◽  
J. Merino ◽  
Ian P. McCulloch ◽  
B. J. Powell
Keyword(s):  
Hubbard Model ◽  
Low Energy ◽  
Effective Theories

scholarly journals The Swampland Conjectures: A Bridge from Quantum Gravity to Particle Physics

Universe ◽  
2021 ◽  
Vol 7 (8) ◽  
pp. 273
Author(s):  
Mariana Graña ◽  
Alvaro Herráez
Keyword(s):  
Effective Field Theories ◽  
Quantum Gravity ◽  
Particle Physics ◽  
Effective Field ◽  
Low Energy ◽  
Field Theories ◽  
Neutrino Masses ◽  
Higgs Potential ◽  
Photon Mass ◽  
Effective Theories

The swampland is the set of seemingly consistent low-energy effective field theories that cannot be consistently coupled to quantum gravity. In this review we cover some of the conjectural properties that effective theories should possess in order not to fall in the swampland, and we give an overview of their main applications to particle physics. The latter include predictions on neutrino masses, bounds on the cosmological constant, the electroweak and QCD scales, the photon mass, the Higgs potential and some insights about supersymmetry.

scholarly journals Low-energy operators in effective theories

2003 ◽  
Vol 68 (3) ◽  
Author(s):  
C. Felline ◽  
N. P. Mehta ◽  
J. Piekarewicz ◽  
J. R. Shepard
Keyword(s):  
Low Energy ◽  
Effective Theories

scholarly journals Renormalization group consistency and low-energy effective theories

2019 ◽  
Vol 6 (5) ◽  
Author(s):  
Jens Braun ◽  
Marc Leonhardt ◽  
Jan M. Pawlowski
Keyword(s):  
Renormalization Group ◽  
Mean Field ◽  
Bound State ◽  
Field Approximation ◽  
Low Energy ◽  
Mean Field Approximation ◽  
Quantum Field Theories ◽  
Model Calculations ◽  
Effective Models ◽  
Effective Theories

Low-energy effective theories have been used very successfully to study the low-energy limit of QCD, providing us with results for a plethora of phenomena, ranging from bound-state formation to phase transitions in QCD. These theories are consistent quantum field theories by themselves and can be embedded in QCD, but typically have a physical ultraviolet cutoff that restricts their range of validity. Here, we provide a discussion of the concept of renormalization group consistency, aiming at an analysis of cutoff effects and regularization-scheme dependences in general studies of low-energy effective theories. For illustration, our findings are applied to low-energy effective models of QCD in different approximations including the mean-field approximation. More specifically, we consider hot and dense as well as finite systems and demonstrate that violations of renormalization group consistency affect significantly the predictive power of the corresponding model calculations.

scholarly journals Dynamical Charge Structure Factor of a One-Dimensional Ionic Hubbard Model in the Low-Energy Region

2019 ◽  
Vol 88 (5) ◽  
pp. 054709
Author(s):  
Yuhei Komaki ◽  
Yuma Iwase ◽  
Shogo Yanagimatsu ◽  
Yoshiyuki Muta ◽  
Nobuya Maeshima ◽  
...  
Keyword(s):  
Hubbard Model ◽  
Structure Factor ◽  
Energy Region ◽  
Low Energy ◽  
Charge Structure ◽  
One Dimensional ◽  
Ionic Hubbard Model ◽  
Dynamical Charge

scholarly journals Effective Field Theories

Particles ◽  
2020 ◽  
Vol 3 (2) ◽  
pp. 245-271 ◽  
Author(s):  
Andrey Grozin
Keyword(s):  
Effective Field Theories ◽  
Degrees Of Freedom ◽  
Effective Field ◽  
Low Energy ◽  
Field Theories ◽  
Alternative View ◽  
Heavy Particles ◽  
Technical Complications ◽  
Effective Theories

This paper represents a pedagogical introduction to low-energy effective field theories. In some of them, heavy particles are “integrated out” (a typical example—the Heisenberg–Euler EFT); in some, heavy particles remain but some of their degrees of freedom are “integrated out” (Bloch–Nordsieck EFT). A large part of these lectures is, technically, in the framework of QED. QCD examples, namely decoupling of heavy flavors and HQET, are discussed only briefly. However, effective field theories of QCD are very similar to the QED case, and there are just some small technical complications: more diagrams, color factors, etc. The method of regions provides an alternative view at low-energy effective theories; this is also briefly introduced.

Renormalization from Density Functional Theory to Strong Coupling Models for the Electronic Structure of La2CuO4

1989 ◽  
Vol 169 ◽  
Author(s):  
Mark S. Hybertsen ◽  
Michael Schluter ◽  
E.B. Stechel ◽  
D.R. Jennison
Keyword(s):  
Electronic Structure ◽  
Hubbard Model ◽  
Strong Coupling ◽  
Density Functional ◽  
Nearest Neighbor ◽  
Quantitative Agreement ◽  
Energy Scale ◽  
Low Energy ◽  
Energy Spectra ◽  
Functional Theory

AbstractStrong coupling models for the electronic structure of La2CuO4 are derived in two successive stages of renormalization. First, a three-band Hubbard model is derived using a constrained density functional approach. Second, exact diagonalization studies of finite clusters within the three band Hubbard model are used to select and map the low energy spectra onto effective one-band Hamiltonians. At each stage, some observables are calculated and found to be in quantitative agreement with experiment. The final results suggest the following models to be adequate descriptions of the low energy scale dynamics: (1) a spin 1/2 Heisenberg model for the insulating case with nearest neighbor J≈130 meV; (2) a "t–t'–J" model with nearly identical parameters for the electron and hole doped cases.

Sign in / Sign up

Export Citation Format

Share Document