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584 Results Found

  • Review
  • Open Access
62 Citations
4,432 Views
52 Pages

Gauge Sector Dynamics in QCD

  • Mauricio Narciso Ferreira and
  • Joannis Papavassiliou

15 February 2023

The dynamics of the QCD gauge sector give rise to non-perturbative phenomena that are crucial for the internal consistency of the theory; most notably, they account for the generation of a gluon mass through the action of the Schwinger mechanism, the...

  • Article
  • Open Access
9 Citations
3,734 Views
14 Pages

A Modal Perturbation Method for Eigenvalue Problem of Non-Proportionally Damped System

  • Danguang Pan,
  • Xiangqiu Fu,
  • Qingjun Chen,
  • Pan Lu and
  • Jinpeng Tan

2 January 2020

The non-proportionally damped system is very common in practical engineering structures. The dynamic equations for these systems, in which the damping matrices are coupled, are very time consuming to solve. In this paper, a modal perturbation method...

  • Feature Paper
  • Article
  • Open Access
39 Citations
4,502 Views
17 Pages

2 July 2020

The Fock space relativistic coupled cluster method (FS-RCC) is one of the most promising tools of electronic structure modeling for atomic and molecular systems containing heavy nuclei. Until recently, capabilities of the FS-RCC method were severely...

  • Review
  • Open Access
1 Citations
2,172 Views
58 Pages

Non-Perturbative Approaches to Linear and Nonlinear Responses of Atoms, Molecules, and Molecular Aggregates: A Theoretical Approach to Molecular Quantum Information and Quantum Biology

  • Satoru Yamada,
  • Takao Kobayashi,
  • Masahiro Takahata,
  • Hiroya Nitta,
  • Hiroshi Isobe,
  • Takashi Kawakami,
  • Shusuke Yamanaka,
  • Mitsutaka Okumura and
  • Kizashi Yamaguchi

7 October 2025

Non-perturbative approaches to linear and nonlinear responses (NLR) of atoms, molecules, and molecular aggregates are reviewed in relation to low and high harmonic generations (HG) by laser fields. These response properties are effective for the gene...

  • Review
  • Open Access
3 Citations
2,743 Views
24 Pages

QCD Effective Locality: A Theoretical and Phenomenological Review

  • Herbert M. Fried,
  • Yves Gabellini,
  • Thierry Grandou and
  • Peter H. Tsang

7 December 2021

About ten years ago, the use of standard functional manipulations was demonstrated to imply an unexpected property satisfied by the fermionic Green’s functions of QCD and dubbed Effective Locality. This feature of QCD is non-perturbative, as it...

  • Review
  • Open Access
6 Citations
3,414 Views
14 Pages

5 February 2019

The two- and three-body contacts are central to a set of univeral relations between microscopic few-body physics within an ultracold Bose gas and its thermodynamical properties. They may also be defined in trapped few-particle systems, which is the s...

  • Article
  • Open Access
9 Citations
3,043 Views
8 Pages

3 August 2019

Although the Asymptotic Safety scenario is one of the most promising approaches to quantum gravity, little attention has been devoted to the issue of the vacuum state. Higher derivative operators often appear on the ultraviolet critical surface aroun...

  • Article
  • Open Access
11 Citations
3,251 Views
36 Pages

24 November 2022

The KdV equation has special significance as it describes various physical phenomena. In this paper, we use two methods, namely, a variational homotopy perturbation method and a classical finite-difference method, to solve 1D and 2D KdV equations wit...

  • Article
  • Open Access
5 Citations
2,622 Views
14 Pages

30 August 2021

In this article, we use the homotopy perturbation transform method to find the fractional Kersten–Krasil’shchik coupled Korteweg–de Vries (KdV) non-linear system. This coupled non-linear system is typically used to describe electric circuits, traffic...

  • Review
  • Open Access
3 Citations
3,808 Views
29 Pages

We dwell upon certain points concerning the meaning of quantum field theory: the problems with the perturbative approach, and the question raised by ’t Hooft of the existence of the theory in a well-defined (rigorous) mathematical sense, as well as s...

  • Article
  • Open Access
6 Citations
1,374 Views
6 Pages

1 August 2003

A simply supported Euler-Bernoulli beam with an intermediate support is considered. The concept of non-ideal boundary conditions is applied to the beam problem. In accordance, the intermediate support is assumed to allow small deflections. Approximat...

  • Article
  • Open Access
1,740 Views
18 Pages

RPCGB Method for Large-Scale Global Optimization Problems

  • Abderrahmane Ettahiri and
  • Abdelkrim El Mouatasim

18 June 2023

In this paper, we propose a new approach for optimizing a large-scale non-convex differentiable function subject to linear equality constraints. The proposed method, RPCGB (random perturbation of the conditional gradient method with bisection algorit...

  • Review
  • Open Access
76 Citations
27,652 Views
64 Pages

Emergence of Hadron Mass and Structure

  • Minghui Ding,
  • Craig D. Roberts and
  • Sebastian M. Schmidt

11 January 2023

Visible matter is characterised by a single mass scale; namely, the proton mass. The proton’s existence and structure are supposed to be described by quantum chromodynamics (QCD); yet, absent Higgs boson couplings, chromodynamics is scale-invariant....

  • Article
  • Open Access
1 Citations
844 Views
20 Pages

On the Yang-Mills Propagator at Strong Coupling

  • Yves Gabellini,
  • Thierry Grandou and
  • Ralf Hofmann

10 February 2025

About twelve years ago, the use of standard functional manipulations was demonstrated to imply an unexpected property satisfied by the fermionic Green’s functions of QCD. This non-perturbative phenomenon has been dubbed an effective locality. I...

  • Article
  • Open Access
108 Citations
6,884 Views
12 Pages

5 October 2015

In this article, the local fractional Homotopy perturbation method is utilized to solve the non-homogeneous heat conduction equations. The operator is considered in the sense of the local fractional differential operator. Comparative results between...

  • Review
  • Open Access
9 Citations
4,202 Views
34 Pages

Dirac, Majorana, Weyl in 4D

  • Loriano Bonora,
  • Roberto Soldati and
  • Stav Zalel

4 August 2020

This is a review of some elementary properties of Dirac, Weyl and Majorana spinors in 4D. We focus in particular on the differences between massless Dirac and Majorana fermions, on one side, and Weyl fermions, on the other. We review in detail the de...

  • Article
  • Open Access
19 Citations
2,715 Views
20 Pages

29 June 2021

This paper deals with non-perturbed and perturbed systems of nonlinear differential systems of first order with multiple time-varying delays. Here, for the considered systems, easily verifiable and applicable uniformly asymptotic stability, integrabi...

  • Feature Paper
  • Article
  • Open Access
2,582 Views
14 Pages

1 March 2022

The NJL model of one-flavor quark is employed to study the properties of QCD mater with finite temperature, external magnetic field, and chiral chemical potential. Through the mean-field approximation and a self-consistent method, a non-perturbative...

  • Article
  • Open Access
48 Citations
3,121 Views
36 Pages

Non-Perturbative Propagators in Quantum Gravity

  • Benjamin Knorr and
  • Marc Schiffer

We employ non-perturbative renormalisation group methods to compute the full momentum dependence of propagators in quantum gravity in general dimensions. We disentangle all different graviton and Faddeev–Popov ghost modes and find qualitative differe...

  • Article
  • Open Access
22 Citations
3,475 Views
16 Pages

Mathematical Analysis of Pseudoplastic Polymers during Reverse Roll-Coating

  • Fateh Ali,
  • Yanren Hou,
  • Muhammad Zahid and
  • Muhammad Afzal Rana

6 October 2020

This article presents a mathematical model and theoretical analysis of coating of a thin film of non-Newtonian polymers as they travel through a small space between two reverse-rotating rolls. The dimensionless forms of the governing equations are si...

  • Article
  • Open Access
11 Citations
2,534 Views
14 Pages

10 February 2022

In this paper, least squares homotopy perturbation is presented as a straightforward and accurate method to compute approximate analytical solutions for systems of ordinary differential equations. The method is employed to solve a problem related to...

  • Article
  • Open Access
7 Citations
2,441 Views
31 Pages

25 June 2021

A finite-horizon two-person non-zero-sum differential game is considered. The dynamics of the game is linear. Each of the players has a quadratic functional on its own disposal, which should be minimized. The case where weight matrices in control cos...

  • Article
  • Open Access
10 Citations
5,006 Views
10 Pages

2 March 2022

We investigate the properties of a dilute gas of impurities embedded in an ultracold gas of bosons that forms a Bose–Einstein condensate (BEC). This work focuses mainly on the equation of state (EoS) of the impurity gas at zero temperature and...

  • Article
  • Open Access
8 Citations
2,778 Views
16 Pages

Color CCD High-Temperature Measurement Method Based on Matrix Searching

  • Chao Li,
  • Deren Kong,
  • Yongjuan Wang,
  • Liming Gao,
  • Xiangyong Zhang and
  • Qi Zhang

24 April 2023

High-temperature processes can have a direct impact on the state and physicochemical properties of materials, making high-temperature measurements important in scientific research, materials processing, and equipment evaluation. A temperature measure...

  • Article
  • Open Access
3,439 Views
15 Pages

Saturation of Energy Levels of the Hydrogen Atom in Strong Magnetic Field

  • Tiago C. Adorno,
  • Dmitry M. Gitman and
  • Anatoly E. Shabad

5 November 2020

We demonstrate that the finiteness of the limiting values of the lower energy levels of a hydrogen atom under an unrestricted growth of the magnetic field, into which this atom is embedded, is achieved already when the vacuum polarization (VP) is cal...

  • Feature Paper
  • Article
  • Open Access
5 Citations
5,096 Views
24 Pages

Toward an Automated-Algebra Framework for High Orders in the Virial Expansion of Quantum Matter

  • Aleks J. Czejdo,
  • Joaquin E. Drut,
  • Yaqi Hou and
  • Kaitlyn J. Morrell

The virial expansion provides a non-perturbative view into the thermodynamics of quantum many-body systems in dilute regimes. While powerful, the expansion is challenging as calculating its coefficients at each order n requires analyzing (if not solv...

  • Article
  • Open Access
229 Views
19 Pages

27 February 2026

Weakly nonlinear oscillators display complex behavior that perturbation methods struggle to analyze, particularly near critical thresholds. The non-perturbation approach (NPA) offers a unified, parameter-agnostic approach that is effective in strongl...

  • Review
  • Open Access
4 Citations
1,882 Views
112 Pages

Something Anomalies Can Tell About Standard Model and Gravity

  • Loriano Bonora and
  • Stefano Gregorio Giaccari

10 February 2025

This is a review/research paper on anomalies applied in a bottom–up approach to standard model and gravity. It is divided into two parts. The first consists of a proper review of anomalies in quantum field theories. Anomalies are analyzed accor...

  • Article
  • Open Access
7 Citations
5,126 Views
11 Pages

2 March 2019

Photoinduced phase transitions have become a very important field of study with the advent of diverse time-resolved experimental techniques whose time resolution matches the electron, lattice, and spin relaxation dynamics associated with elementary e...

  • Feature Paper
  • Article
  • Open Access
7 Citations
2,085 Views
24 Pages

21 July 2023

A class of exact (non-perturbative) models of strong gravitational waves based on Shapovalov type III spacetimes and Einstein’s vacuum equations is obtained. Exact solutions are found for the trajectories of particles and radiation in a gravita...

  • Article
  • Open Access
8 Citations
2,653 Views
14 Pages

Signal Detection in Nearly Continuous Spectra and ℤ2-Symmetry Breaking

  • Vincent Lahoche,
  • Dine Ousmane Samary and
  • Mohamed Tamaazousti

28 February 2022

The large scale behavior of systems having a large number of interacting degrees of freedom is suitably described using the renormalization group from non-Gaussian distributions. Renormalization group techniques used in physics are then expected to p...

  • Article
  • Open Access
11 Citations
1,118 Views
19 Pages

A Novel Methodology for Scrutinizing Periodic Solutions of Some Physical Highly Nonlinear Oscillators

  • Gamal M. Ismail,
  • Galal M. Moatimid,
  • Stylianos V. Kontomaris and
  • Livija Cveticanin

The study offers a comprehensive investigation of periodic solutions in highly nonlinear oscillator systems, employing advanced analytical and numerical techniques. The motivation stems from the urgent need to understand complex dynamical behaviors i...

  • Review
  • Open Access
6 Citations
3,858 Views
22 Pages

18 January 2019

Computer simulations allow us to explore non-perturbative phenomena in physics. This has the potential to help us understand quantum gravity. Finding a theory of quantum gravity is a hard problem, but, in the last several decades, many promising and...

  • Article
  • Open Access
4 Citations
3,995 Views
23 Pages

Inspecting Non-Perturbative Contributions to the Entanglement Entropy via Wavefunctions

  • Arpan Bhattacharyya,
  • Ling-Yan Hung,
  • Pak Hang Chris Lau and
  • Si-Nong Liu

7 December 2017

In this paper, we would like to systematically explore the implications of non-perturbative effects on entanglement in a many body system. Instead of pursuing the usual path-integral method in a singular space, we attempt to study the wavefunctions i...

  • Feature Paper
  • Article
  • Open Access
9 Citations
3,127 Views
20 Pages

Symmetries of Thirring Models on 3D Lattices

  • Andreas W. Wipf and
  • Julian J. Lenz

6 February 2022

We review some recent developments about strongly interacting relativistic Fermi theories in three spacetime dimensions. These models realize the asymptotic safety scenario and are used to describe the low-energy properties of Dirac materials in cond...

  • Review
  • Open Access
16 Citations
4,850 Views
25 Pages

26 March 2018

The stabilizing effect of quantum fluctuations on the escape process and the relaxation dynamics from a quantum metastable state are investigated. Specifically, the quantum dynamics of a multilevel bistable system coupled to a bosonic Ohmic thermal b...

  • Article
  • Open Access
4 Citations
2,050 Views
15 Pages

Two-Zero Textures Based on A4 Symmetry and Unimodular Mixing Matrix

  • Neda Razzaghi,
  • Seyed Meraj Mousavi Rasouli,
  • Paulo Parada and
  • Paulo Moniz

14 November 2022

We propose a phenomenological model of two-zeros Majorana neutrino mass matrix based on the A4 symmetry, where the structure of mixing matrix is a unimodular second scheme of trimaximal TM2, and the charged lepton mass matrix is diagonal. We show tha...

  • Article
  • Open Access
4,568 Views
26 Pages

The Inverse-Square Interaction Phase Diagram: Unitarity in the Bosonic Ground State

  • Grigori E. Astrakharchik,
  • P. S. Kryuchkov,
  • I. L. Kurbakov and
  • Yu. E. Lozovik

8 June 2018

Ground-state properties of bosons interacting via inverse square potential (three dimensional Calogero-Sutherland model) are analyzed. A number of quantities scale with the density and can be naturally expressed in units of the Fermi energy and Fermi...

  • Abstract
  • Open Access
2,392 Views
1 Page

Nonperturbative QED on the Hopf Bundle

  • Vladimir Dzhunushaliev and
  • Vladimir Folomeev

We consider the Dirac equation and Maxwell’s electrodynamics in ×S3 spacetime, where a three-dimensional sphere is the Hopf bundle S3S2. The method of nonperturbative quantization of interacting Dirac and Maxwell fields is suggested. The correspond...

  • Review
  • Open Access
23 Citations
6,679 Views
74 Pages

Systematic Quantum Cluster Typical Medium Method for the Study of Localization in Strongly Disordered Electronic Systems

  • Hanna Terletska,
  • Yi Zhang,
  • Ka-Ming Tam,
  • Tom Berlijn,
  • Liviu Chioncel,
  • N. S. Vidhyadhiraja and
  • Mark Jarrell

26 November 2018

Great progress has been made in recent years towards understanding the properties of disordered electronic systems. In part, this is made possible by recent advances in quantum effective medium methods which enable the study of disorder and electron-...

  • Article
  • Open Access
2,376 Views
21 Pages

Nonperturbative Quantization Approach for QED on the Hopf Bundle

  • Vladimir Dzhunushaliev and
  • Vladimir Folomeev

We consider the Dirac equation and Maxwell’s electrodynamics in R×S3 spacetime, where a three-dimensional sphere is the Hopf bundle S3S2. In both cases, discrete spectra of classical solutions are obtained. Based on the solutions obtained, the quant...

  • Article
  • Open Access
4 Citations
2,527 Views
16 Pages

30 October 2018

In this article, we present up to date results on the balanced model reduction techniques for linear control systems, in particular the singular perturbation approximation. One of the most important features of this method is it allows for an a prior...

  • Article
  • Open Access
12 Citations
4,451 Views
23 Pages

16 April 2019

On the basis of the well-known kinetic description of e e + vacuum pair creation in strong electromagnetic fields in D = 3 + 1 QED we construct a nonperturbative kinetic approach to electron-hole excitations in graphene un...

  • Article
  • Open Access
6 Citations
790 Views
32 Pages

29 September 2025

By applying the Non-Perturbative Approach (NPA), the corresponding linear differential equation is obtained. Aimed at organizational investigation, the resulting linear equation is used. Strong agreement between numerical calculations and the precise...

  • Article
  • Open Access
10 Citations
3,232 Views
20 Pages

Non-Singular Finite Time Tracking Control Approach Based on Disturbance Observers for Perturbed Quadrotor Unmanned Aerial Vehicles

  • Fayez F. M. El-Sousy,
  • Khalid A. Alattas,
  • Omid Mofid,
  • Saleh Mobayen,
  • Jihad H. Asad,
  • Paweł Skruch and
  • Wudhichai Assawinchaichote

5 April 2022

In this paper, a disturbance observer based on the non-singular terminal sliding mode control method was presented for the quadrotor in the presence of wind perturbation. First, the position and attitude dynamical equation of the quadrotor was introd...

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