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Related papers: One-Loop Threshold Effects in String Unification

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We study radiative corrections to the mass spectrum and the triple Higgs boson coupling in the model with an additional Y=1 triplet field. In this model, the vacuum expectation value for the triplet field is strongly constrained from the…

High Energy Physics - Phenomenology · Physics 2015-06-04 Mayumi Aoki , Shinya Kanemura , Mariko Kikuchi , Kei Yagyu

In this paper, we study a CPT-even Lorentz-breaking extension of the scalar QED. For this theory, we calculate the one-loop lower-order contributions in the Lorentz-violating parameters to the two-point functions of scalar and gauge fields.…

High Energy Physics - Theory · Physics 2022-07-07 A. P. Baêta Scarpelli , J. C. C. Felipe , L. C. T. Brito , A. Yu. Petrov

We investigate whether the hypercharge assignments in the Standard Model can be interpreted as a hint at Grand Unification in the context of heterotic string theory. To this end, we introduce a general method to calculate U(1)_Y for any…

High Energy Physics - Theory · Physics 2008-11-26 S. Raby , A. Wingerter

We make an estimate of the quadratic correction based on gauge/string duality. Like in QCD, it proves to be negative and proportional to the string tension.

High Energy Physics - Theory · Physics 2009-11-11 Oleg Andreev

We revisit the computation (hep-th/0306130) of 1-loop AdS_5 x S^5 superstring sigma model correction to energy of a closed circular string rotating in S^5. The string is spinning around its center of mass with two equal angular momenta…

High Energy Physics - Theory · Physics 2009-09-17 S. A. Frolov , I. Y. Park , A. A. Tseytlin

We present the beta functions of gauge and Yukawa couplings in general four-dimensional quantum field theory, at four and three loops, respectively. The essence of our approach is fixing unknown coefficients in the most general ansatz for…

High Energy Physics - Phenomenology · Physics 2021-07-28 Alexander Bednyakov , Andrey Pikelner

We calculate explicitly the one-loop effective potential in different Lorentz-breaking field theory models. First, we consider a Yukawa-like theory and, then, some examples of Lorentz-violating extensions of scalar QED. We observed, for the…

High Energy Physics - Theory · Physics 2018-01-17 A. P. Baeta Scarpelli , L. C. T. Brito , J. C. C. Felipe , J. R. Nascimento , A. Yu. Petrov

We present a new scenario for gauge coupling unification in flipped SU(5) string models, which identifies the $M_{32}$ scale of SU(3) and SU(2) unification with the empirical $M_{\rm LEP}\sim10^{15-16}$~GeV scale, and the $M_{51}$ scale of…

High Energy Physics - Phenomenology · Physics 2009-10-28 J. Lopez , D. Nanopoulos

We study radiative corrections to third generation scalar fermions into gauge bosons $Z$ and $W^\pm$. We include both SUSY-QCD, QED and full electroweak corrections. It is found that the electroweak corrections can be of the same order as…

High Energy Physics - Phenomenology · Physics 2008-11-26 Abdesslam Arhrib , Rachid Benbrik

We study asymptotically non-free gauge theories and search for renormalization group invariant (i.e. technically natural) relations among the couplings which lead to successful gauge-Yukawa unification. To be definite, we consider a…

High Energy Physics - Theory · Physics 2009-10-28 Jisuke Kubo , Myriam Mondragon , Nicholas D. Tracas , George Zoupanos

In this paper we extend the study initiated in arXiv:2302.04709v2 [hep-th] to the computation of one-loop elastic amplitudes. We consider 1+1 dimensional massive bosonic Lagrangians with polynomial-like potentials and absence of inelastic…

High Energy Physics - Theory · Physics 2024-03-08 Matheus Fabri , Davide Polvara

Recently, it was demonstrated that one-loop energy shifts of spinning superstrings on AdS5xS5 agree with certain Bethe equations for quantum strings at small effective coupling. However, the string result required artificial regularization…

High Energy Physics - Theory · Physics 2010-04-06 N. Beisert , A. A. Tseytlin

The response of the one loop effective action for a gauge theory with local couplings $g(x),\theta(x)$ under a local Weyl rescaling of the background metric is calculated. Apart from terms which may be removed by local contributions to the…

High Energy Physics - Theory · Physics 2009-11-10 Hugh Osborn

Loop Tree Duality (LTD) offers a promising avenue to numerically integrate multi-loop integrals directly in momentum space. It is well-established at one loop, but there have been only sparse numerical results at two loops. We provide a…

High Energy Physics - Phenomenology · Physics 2019-10-16 Zeno Capatti , Valentin Hirschi , Dario Kermanschah , Ben Ruijl

We identify a large class of one-loop amplitudes for massless particles that can be constructed via unitarity from tree amplitudes, without any ambiguities. One-loop amplitudes for massless supersymmetric gauge theories fall into this…

High Energy Physics - Phenomenology · Physics 2010-11-15 Z. Bern , L. Dixon , D. C. Dunbar , D. A. Kosower

In this contribution to the Proceedings of the Conference on Analysis, Complex Geometry, and Mathematical Physics, an expository overview of superstring perturbation theory to two loop order is presented to an audience of mathematicians and…

High Energy Physics - Theory · Physics 2014-04-01 Eric D'Hoker

The Loop-Tree Duality (LTD) is a novel perturbative method in QFT that establishes a relation between loop-level and tree-level scattering amplitudes. This is achieved by directly applying the Residue Theorem to the loop-energy-integration.…

High Energy Physics - Phenomenology · Physics 2015-09-25 Sebastian Buchta

A gauge theory with an underlying SU_q(2) quantum group symmetry is introduced, and its properties examined. With suitable assumptions, this model is found to have many similarities with the usual SU(2)\times U(1) Standard Model,…

High Energy Physics - Theory · Physics 2009-10-30 Paul Watts

We compute the full set of weak-scale gauge and Yukawa threshold corrections in the minimal supersymmetric standard model, and use them to study the effects of the supersymmetric particle spectrum on gauge and Yukawa coupling unification.

High Energy Physics - Phenomenology · Physics 2016-09-01 J. Bagger , K. Matchev , D. Pierce

We compute, in the MSSM framework, the sum of the one-loop electroweak and of the total QED radiation effects for the process $pp \to t W+X$, initiated by the parton process $bg\to tW$. Combining these terms with the existing NLO…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Beccaria , C. M. Carloni Calame , G. Macorini , G. Montagna , F. Piccinini , F. M. Renard , C. Verzegnassi