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Related papers: Chiral Vacuum Alignment and Spontaneous CP Violati…

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We consider the issue of vacuum misalignment induced by four-Fermi couplings in a generic strongly coupled four-dimensional gauge theory. After briefly reviewing the general formalism, we focus on the case of partial compositness-like…

High Energy Physics - Phenomenology · Physics 2023-05-17 Avik Banerjee , Gabriele Ferretti

One common way to define spontaneous symmetry breaking involves explicit symmetry breaking. This definition can be used in any approach to Effective Field Theory, from perturbation theory to lattice simulations. It allows us to study the…

High Energy Physics - Phenomenology · Physics 2017-10-23 Leonardo Pedro

We reconsider in this paper the old aim of trying to understand if the observed realization of discrete symmetries as Parity or CP in the QCD vacuum can be satisfied from first principles. We show how under the appropriate assumptions…

High Energy Physics - Theory · Physics 2014-11-18 V. Azcoiti , G. di Carlo , A. Vaquero

Indirect CP violation is analyzed in the framework of the electroweak gauge theory of J=0 mesons proposed in ref.[1], in which they transform like composite fermion-antifermion operators by the chiral U(N)left x U(N)right group and by the…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. Machet

We numerically study the phase structure of the two-flavor Schwinger model with matrix product states, focusing on the (1+1)-dimensional analog of the CP-violating Dashen phase in QCD. We simulate the two-flavor Schwinger model around the…

High Energy Physics - Lattice · Physics 2023-08-10 Lena Funcke , Karl Jansen , Stefan Kühn

We study spontaneous symmetry breaking in quantum field theories with fermionic order parameters and construct, for the first time in the literature, the constraint effective potential for it. The Grassmann-valued constraint we encounter is…

High Energy Physics - Lattice · Physics 2024-12-18 Gergely Endrődi , Tamás G. Kovács , Gergely Markó , Laurin Pannullo

A novel, nonperturbative, way to generate chiral symmetry breaking within the linear sigma model for 3 flavours is discussed. After spontaneous chiral symmetry breaking in the vacuum at the tree level the scalar nonet obtains mass, while…

High Energy Physics - Phenomenology · Physics 2009-10-30 Nils A. Tornqvist

We present a natural solution to the strong CP problem in the context of split fermions. By assuming CP is spontaneously broken in the bulk, a weak CKM phase is created in the standard model due to a twisting in flavor space of the bulk…

High Energy Physics - Phenomenology · Physics 2010-02-03 Roni Harnik , Gilad Perez , Matthew D. Schwartz , Yuri Shirman

We build a class of invisible axion models with tree-level Flavor Changing Neutral Currents completely controlled by the fermion mixing matrices. The scalar sector of these models contains three-Higgs doublets and a complex scalar gauge…

High Energy Physics - Phenomenology · Physics 2015-01-07 Alejandro Celis , Javier Fuentes-Martin , Hugo Serodio

Chiral symmetry breaking (ChSB) is reviewed to some extent within the quark-level-linear-sigma-model (QLL$\sigma$M) theory and standard chiral perturbation theory (ChPT). It is shown, on the basis of several examples related to the pion, as…

High Energy Physics - Phenomenology · Physics 2007-05-23 Michael D. Scadron , Frieder Kleefeld , George Rupp

We investigate a proposal to address several outstanding shortcomings of the perturbative Standard Model (SM) of particle physics. The appeal of this proposal is that these features are a manifestation of the non-perturbative sector of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. D. Bashford

We have carried out numerical studies of vacuum alignment in technicolor models of electroweak and flavor symmetry breaking. The goal is to understand alignment's implications for strong and weak CP nonconservation in quark interactions. In…

High Energy Physics - Phenomenology · Physics 2009-10-31 Kenneth Lane , Tonguc Rador , Estia Eichten

We study how to incorporate CP violation in the Froggatt--Nielsen (FN) mechanism. To this end, we introduce non-renormalizable interactions with a flavor democratic structure to the fermion mass generation sector. It is found that at least…

High Energy Physics - Phenomenology · Physics 2008-11-26 Shinya Kanemura , Koichi Matsuda , Toshihiko Ota , Serguey Petcov , Tetsuo Shindou , Eiichi Takasugi , Koji Tsumura

We study chiral symmetry breaking for fundamental charged fermions coupled electromagnetically to photons with the inclusion of four-fermion contact self-interaction term. We employ multiplicatively renormalizable models for the photon…

High Energy Physics - Phenomenology · Physics 2013-05-30 F. Akram , A. Bashir , L. X. Gutierrez-Guerrero , B. Masud , J. Rodriguez-Quintero , C. Calcaneo-Roldan , M. E. Tejeda-Yeomans

In the limit of vanishing up, down and strange quark masses, QCD exhibits a chiral symmetry. This symmetry is broken spontaneously to its vector subgroup, giving rise to Goldstone bosons. These acquire a small mass through the explicit…

High Energy Physics - Phenomenology · Physics 2024-12-31 Ulf-G. Meißner

We discuss the origin of CP violation in settings with a discrete (flavor) symmetry $G$. We show that physical CP transformations always have to be class-inverting automorphisms of $G$. This allows us to categorize finite groups into three…

High Energy Physics - Phenomenology · Physics 2015-06-18 Mu-Chun Chen , Maximilian Fallbacher , K. T. Mahanthappa , Michael Ratz , Andreas Trautner

We consider chiral perturbation theory (ChPT) with a non-zero theta term. Due to the CP violating term, the vacuum of chiral fields is shifted to a non-trivial element on the SU(N_f) group manifold. The CP violation also provides mixing of…

High Energy Physics - Lattice · Physics 2014-11-20 Sinya Aoki , Hidenori Fukaya

Dynamical nature of the gauge degree of freedom and its effect to fermion spectrum are studied for four-dimensional nonabelian chiral gauge theory in the vacuum overlap formulation. The covariant gauge fixing term and the Faddeev-Popov…

High Energy Physics - Lattice · Physics 2007-05-23 Yoshio Kikukawa

With the help of the functional integration method, the formation of scalar, pseudoscalar condensates, and dynamical symmetry breaking in the U(3) four-fermion model has been investigated. We show the possibility of spontaneous CP symmetry…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. I. Kruglov

We present a model based on the $SU(3)_C\otimes SU(3)_L\otimes U(1)_X$ gauge symmetry that relates the mass hierarchy of the fermions with the solution to the strong CP problem through the $U(1)_{PQ}$ Peccei-Quinn symmetry. This last…

High Energy Physics - Phenomenology · Physics 2018-12-19 A. G. Dias , J. Leite , D. D. Lopes , C. C. Nishi