Related papers: The Equivalence Theorem and Effective Lagrangians
The equivalence theorem states that the leading part of the amplitude for a process with external longitudinally polarized vector bosons is given by the amplitude in which the longitudinal vector bosons are replaced by the corresponding…
The precise statement of the equivalence theorem, between the longitudinally polarized states of a massive gauge boson and the corresponding goldstone mode, is discussed when the amplitude in question depends on masses of other particles…
In the presence of some forms of global anomalies, the equivalence theorem, which relates the interactions of longitudinal gauge bosons to those of the Goldstone bosons, is not always valid. This can occur when the Goldstone sector contains…
A non-linear sigma model effective lagrangian is analyzed for theories in which supersymmetry is softly broken at scales below the electroweak symmetry breaking scale. Besides the gauge and matter supermultiplets, the low energy theory…
Effective theories provide a powerful tool for testing the Standard Model and for searching for the effects of new physics in a model-independent manner. In general one assumes that the effects of new physics characterized by a high-energy…
We formulate the equivalence between the longitudinal weak-boson and the Goldstone boson as a criterion for sensitively probing the electroweak symmetry breaking mechanism and develop a precise power counting rule for chiral Lagrangian…
The calculation of the leading electroweak corrections to physical transition matrix elements in powers of $M_H^2/v^2$ can be greatly simplified in the limit $M_H^2\gg M_W^2,\, M_Z^2$ through the use of the Goldstone boson equivalence…
An Effective Lagrangian description is useful for describing potential physics beyond the Standard Model. The method is illustrated by reference to interactions among the electroweak bosons ($W^\pm$ \& $Z^0$). The resulting estimates of the…
Based upon our recent study, we reveal the profound physical content of the longitudinal-Goldstone boson equivalence theorem as being able to discriminate physical processes which are sensitive/insensitive to probing the electroweak…
The Equivalence Theorem is commonly used to calculate perturbatively amplitudes involving gauge bosons at energy scales higher than gauge boson masses. However, when the scalar sector is strongly interacting the theory is non-perturbative.…
A pedagogical introduction to the equivalence theorem for longitudinal vector bosons in electroweak theories is presented and the problem of high-energy behaviour of scattering amplitudes in the Standard Model is briefly reviewed. To make…
We present an Equivalence Theorem for the longitudinal components of the gauge bosons in a compactified five dimensional extension of the Standard Model, whose spontaneous symmetry breaking is driven either by one Higgs in the bulk or by…
A simple derivation of the distributions of the equivalent electroweak vector bosons in leptons and quarks is presented. The applicability of the equivalent vector boson approximation at relatively low energies close to the $W$ and $Z$…
The high-energy behavior of vector-boson scattering amplitudes is examined within an effective theory for non-standard self-interactions of electroweak vector-bosons. Irrespectively of whether this theory is brought into a gauge invariant…
Effective Lagrangians were originally used only at the tree level as so-called phenomenological Lagrangians since they were in general non-renormalizable. Today they are treated as effective field theories valid below a characteristic…
This article presents a number of technical tools and results that may be instrumental to discern the nature of the Higgs particle. In scenarios where an additional strongly interacting sector is present in the electroweak theory resulting…
Effective Lagrangians are a useful tool for a data-driven approach to physics beyond the Standard Model at the LHC. However, for the new physics scales accessible at the LHC, the effective operator expansion is only relatively slowly…
In the standard model with electroweak symmetry breaking through the Higgs mechanism, electroweak gauge-boson scattering amplitudes are large if the Higgs boson is heavy, and electroweak gauge interactions become strong. In theories with…
The claimed finding of a light Higgs boson makes the minimal Standard Model unitary. Yet we recall that the general low-energy dynamics for the minimal electroweak symmetry breaking sector with three Goldstone bosons and one light scalar is…
I describe a novel covariant formulation of massive gauge theories in which the longitudinal polarization vectors do not grow with the energy. Therefore in the present formalism, differently from the ordinary one, the energy and coupling…