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Related papers: Second Order Fermions in Gauge Theories

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Scattering amplitudes are often split up into their color (su(N)) and kinematic components. Since the su(N) gauge part can be described using flows of color, one may anticipate that the double su(2) kinematic part can be described in terms…

High Energy Physics - Phenomenology · Physics 2022-04-27 Joakim Alnefjord , Andrew Lifson , Christian Reuschle , Malin Sjodahl

Using the newly modified method developed for symbolic evaluation of Feynman amplitudes we examine two processes $2\to 2$ (including a case of Majorana fermions) at a tree level. Constructing special polarization basis for spinor particles,…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Cherzor

Generalized Dilaton Theories in two dimensions coupled to Dirac fermions are subjected to constraint analysis. Three first class secondary constraints are found, corresponding to one local Lorentz symmetry and two diffeomorphisms. Moreover,…

High Energy Physics - Theory · Physics 2007-05-23 Rene Meyer

We discuss fermion coupling in the framework of spinfoam quantum gravity. We analyze the gravity-fermion spinfoam model and its fermion correlation functions. We show that there is a spinfoam analog of PCT symmetry for the fermion fields on…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Muxin Han , Carlo Rovelli

We review our efforts in investigating gauge theories with fermions in the adjoint representation of the gauge group by means of numerical simulations. These theories have applications in possible extensions of the Standard Model of…

High Energy Physics - Lattice · Physics 2022-12-23 Georg Bergner , Gernot Münster , Stefano Piemonte

Both algebras, Clifford and Grassmann, offer "basis vectors" for describing the internal degrees of freedom of fermions. The oddness of the "basis vectors", transferred to the creation operators, which are tensor products of the finite…

General Physics · Physics 2020-12-16 N. S. Mankoc Borstnik , H. B. F. Nielsen

We consider the quantum theory of the Lorentzian fermionic differential forms and the corresponding bi-spinor quantum fields, which are the expansion coefficients of the forms in the bi-spinor basis of Becher and Joos [7]. The canonical…

High Energy Physics - Phenomenology · Physics 2020-02-05 Alex Jourjine

The sign cancellation between scattering amplitudes makes fermions different from bosons. We systematically investigate Feynman diagrams' fermionic sign structure in a representative many-fermion system---a uniform Fermi gas with Yukawa…

Quantum Gases · Physics 2021-03-31 Bao-Zong Wang , Peng-Cheng Hou , Youjin Deng , Kristjan Haule , Kun Chen

We discuss a remarkable new approach initiated by Cachazo, Svrcek and Witten for calculating gauge theory amplitudes. The formalism amounts to an effective scalar perturbation theory which in many cases offers a much simpler alternative to…

High Energy Physics - Theory · Physics 2017-08-23 Valentin V. Khoze

Fermions are coupled to the Einstein-Cartan system in the canonical formulation, including the cosmological, the Barbero-Immirzi, and the non-minimal coupling constants. The resulting ten first-class constraints generate gauge…

General Relativity and Quantum Cosmology · Physics 2025-12-02 Erick I. Duque

The Fermi function is historically derived from the Dirac equation or the Schr\"odinger equation. However, we claim that the Fermi function should be derived from quantum field theory. Then, we obtain the following results: (1) We give the…

High Energy Physics - Theory · Physics 2014-07-25 Akihiro Matsuzaki , Hidekazu Tanaka

We show that the Dirac dressing of the fermion is equivalent to a shift of the gauge parameter. For every gauge, the gauge-dependent part is projected out of physical observables. After renormalization, the physical mass is the same for…

High Energy Physics - Theory · Physics 2026-03-18 Kang-Sin Choi

Accounting for all the relativistic effects, we have developed the fully nonlinear gauge-invariant formalism for describing the cosmological observables and presented the second-order perturbative expressions associated with light…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-03 Matteo Magi , Jaiyul Yoo

We summarize our recent work on gauge theories with two flavors of fermions in the two-index symmetric representation: SU(2) gauge theory with adjoint fermions, SU(3) with sextets, and SU(4) with ten-dimensional-representation fermions. All…

High Energy Physics - Lattice · Physics 2011-11-02 Thomas DeGrand , Yigal Shamir , Benjamin Svetitsky

An alternative to commonly used domain wall fermions is presented. Some rigorous bounds on the condition number of the associated linear problem are derived. On the basis of these bounds and some experimentation it is argued that domain…

High Energy Physics - Lattice · Physics 2009-11-07 H. Neuberger

A specific class of gauge theories is geometrically described in terms of fermions. In particular, it is shown how the geometrical frame presented naturally includes spontaneous symmetry breaking of Yang-Mills gauge theories without making…

Mathematical Physics · Physics 2015-06-26 Juergen Tolksdorf , Torsten Thumstaedter

A non-Abelian gauge field with a topological action is coupled to a spin 3/2 Majorana spinor. The symmetries of this model are analyzed using the Dirac constraint formalism. These symmetries include a Fermionic symmetry and the algebra of…

High Energy Physics - Theory · Physics 2017-11-22 D. G. C. McKeon

We discuss the lattice formulation of gauge theories with fermions in arbitrary representations of the color group, and present the implementation of the RHMC algorithm for simulating dynamical Wilson fermions. A first dataset is presented…

High Energy Physics - Lattice · Physics 2010-01-21 Luigi Del Debbio , Agostino Patella , Claudio Pica

We extend the dipole formalism of Catani and Seymour to QCD processes involving heavy fermions. We give the appropriate subtraction terms together with their integrated counterpart. All calculations are done within dimensional…

High Energy Physics - Phenomenology · Physics 2010-02-03 Lukas Phaf , Stefan Weinzierl

In a recent paper we introduced the chirality-flow formalism, a method for simple and transparent calculations of Feynman diagrams based on the left- and right-chiral $\mathrm{sl}(2,\mathbb{C})$ nature of spacetime. While our previous work…

High Energy Physics - Phenomenology · Physics 2023-03-09 Joakim Alnefjord , Andrew Lifson , Christian Reuschle , Malin Sjodahl