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Related papers: Unitarity bounds and sum rules in the SMEFT

200 papers

We study perturbative unitarity constraints on generic interactions between fermion and vector fields, which are allowed to have generic quantum numbers under a $\prod_i SU(N_i) \otimes U(1)$ group. We derive compact expressions for the…

High Energy Physics - Phenomenology · Physics 2023-09-20 Daniele Barducci , Marco Nardecchia , Claudio Toni

We develop a primal bootstrap framework for effective field theories in the presence of a graviton pole, based on finite-resolution sampling rather than smearing, while also allowing direct control over the number of subtractions. We show…

High Energy Physics - Theory · Physics 2026-04-17 Guangzhuo Peng , Laurentiu Rodina , Anna Tokareva , Yongjun Xu

We derive the complete set of positivity bounds for the leading-twist parton distribution functions (PDFs) of a spin-3/2 hadron for the first time. This work generalizes the Soffer bound, a fundamental constraint for spin-1/2 nucleons, to…

High Energy Physics - Phenomenology · Physics 2026-02-13 Dongyan Fu , Yubing Dong , S. Kumano , Ju-Jun Xie

From the low-energy effective theory of dilatons, consistent with the scale anomaly, we calculate the $2\to2$ scattering amplitudes of dilatons. We find that the one-loop amplitude violates the unitarity bound as the scattering energy…

High Energy Physics - Phenomenology · Physics 2022-10-26 Deog Ki Hong , Gyurin Kim , Jun Beom Park

The electroweak symmetry-breaking sector is one of the most promising and uncharted parts of the Standard Model; but it seems likely that new electroweak physics may be out of reach of the present accelerator effort and the hope is to…

High Energy Physics - Phenomenology · Physics 2023-09-13 Raquel Gomez-Ambrosio , Felipe J. Llanes-Estrada , Alexandre Salas-Bernardez , Juan J. Sanz-Cillero

We study the unitarity bounds of the scattering amplitudes in the extra dimensional gauge theory where the gauge symmetry is broken by the boundary condition. The estimation of the amplitude of the diagram including four massive gauge…

High Energy Physics - Theory · Physics 2014-11-18 Y. Abe , N. Haba , Y. Higashide , K. Kobayashi , M. Matsunaga

The methods of effective field theory are used to explore the theoretical and phenomenological aspects of the torsion field. Spinor action coupled to electromagnetic field and torsion possesses an additional softly broken gauge symmetry.…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. S. Belyaev , I. L. Shapiro

We study a dynamics of ultracold Fermi-gases near the unitary limit in the framework of Effective Field Theory. It is shown that, while one can obtain a reasonable description of the universal proportionality constant both in the narrow and…

Superconductivity · Physics 2008-11-26 Boris Krippa

We apply the general principles of effective field theories to the construction of effective interactions suitable for few- and many-body calculations in a no-core shell model framework. We calculate the spectrum of systems with three and…

Other Condensed Matter · Physics 2008-11-26 I. Stetcu , B. R. Barrett , U. van Kolck , J. P. Vary

We derive constraints on the mixing of heavy right-handed neutrinos with the SM fields in the most general Seesaw scenario where the heavy neutrinos are integrated out. Among the electroweak and flavour observables included in the global…

High Energy Physics - Phenomenology · Physics 2016-11-24 Josu Hernandez-Garcia

We investigate flavour violating four Fermi Standard Model Effective Field Theory (SMEFT) operators of dimension-six that can be probed via $tc ~(\bar{t}c+t\bar{c})$ production at the multi-TeV muon collider. We study different FCNC and…

High Energy Physics - Phenomenology · Physics 2025-05-28 Subhaditya Bhattacharya , Sahabub Jahedi , Soumitra Nandi , Abhik Sarkar

We study whether higher-dimensional operators in effective field theories, in particular in the Standard Model Effective Field Theory (SMEFT), can source gauge anomalies via the modification of the interactions involved in triangle…

High Energy Physics - Phenomenology · Physics 2021-06-30 Quentin Bonnefoy , Luca Di Luzio , Christophe Grojean , Ayan Paul , Alejo N. Rossia

We find the complete set of conditions satisfied by the forward $2\to2$ scattering amplitude in unitarity and causal theories. These are based on an infinite set of energy dependent quantities -- the arcs -- which are dispersively expressed…

High Energy Physics - Theory · Physics 2021-10-12 Brando Bellazzini , Joan Elias Miró , Riccardo Rattazzi , Marc Riembau , Francesco Riva

We use Mellin space dispersion relations together with Polyakov conditions to derive a family of sum rules for Conformal Field Theories (CFTs). The defining property of these sum rules is suppression of the contribution of the double twist…

High Energy Physics - Theory · Physics 2021-06-16 Dean Carmi , Joao Penedones , Joao A. Silva , Alexander Zhiboedov

We develop the geometric formulation of the Standard Model Effective Field Theory (SMEFT). Using this approach we derive all-orders results in the $\sqrt{2 \langle H^\dagger H \rangle}/\Lambda$ expansion relevant for studies of electroweak…

High Energy Physics - Phenomenology · Physics 2020-06-12 Andreas Helset , Adam Martin , Michael Trott

We obtain model independent bounds for the form factors which arise in semileptonic B -> Pi decays. To this end we derive a theoretical restriction for possible combinations of the value of the form factor and its derivatives at the…

High Energy Physics - Phenomenology · Physics 2009-10-31 T. Mannel , B. Postler

Triplet extensions are attractive alternatives to the standard model (SM) of particle physics. While models with only one triplet are highly constrained by electroweak precision observables, this is not necessarily the case once several…

High Energy Physics - Phenomenology · Physics 2018-08-02 Manuel E. Krauss , Florian Staub

Effective Field Theories such as HEFT, organized as momentum expansions, are a controllable approximation to strong dynamics only near threshold, as they miss exact elastic unitarity, reducing their predictive power at a higher scale if…

High Energy Physics - Phenomenology · Physics 2021-12-02 Alexandre Salas-Bernárdez

We show that 10D spinor helicity formalism can be understood as spinor moving frame approach to supersymmetric particles extended to the description of amplitudes. This allows us to develop the spinor helicity formalism for 11D supergravity…

High Energy Physics - Theory · Physics 2018-12-05 Igor Bandos

We consider aspects of tree and one-loop behavior in a generic 4d EFT of massless scalars, fermions, and vectors, with a particular eye to the high-energy limit of the Standard Model EFT at operator dimensions 6 and 8. First, we classify…

High Energy Physics - Phenomenology · Physics 2023-01-10 Nathaniel Craig , Minyuan Jiang , Ying-Ying Li , Dave Sutherland