On the addition of an SU(2) quadruplet of scalars to the Standard Model, by Darius Jurčiukonis, Luís Lavoura

SciPost Physics Core Home Authoring Refereeing Submit a manuscript About On the addition of an SU(2) quadruplet of scalars to the Standard Model Darius Jurčiukonis, Luís Lavoura SciPost Phys. Core 9, 022 (2026) · published 13 April 2026 doi: 10.21468/SciPostPhysCore.9.2.022 pdf BiBTeX RIS Submissions/Reports Abstract We consider the extension of the Standard electroweak Model through an $SU(2)$ quadruplet of scalars with hypercharge either $3/2$ or $1/2$ (with an additional reflection symmetry in the latter case). We establish, through exact analytical equations, the boundaries of the phase spaces of the gauge-invariant terms that appear in the (renormalizable) scalar potentials. We devise procedures for the determination of necessary and sufficient bounded-from-below conditions on those potentials; we emphasize that one mostly needs to scan the scalar potential over a few lines, instead of surfaces, in order to establish the boundedness-from-below; this fact allows one to reduce by three orders of magnitude the computational time devoted to that establishment. × TY - JOURPB - SciPost FoundationDO - 10.21468/SciPostPhysCore.9.2.022TI - On the addition of an SU(2) quadruplet of scalars to the Standard ModelPY - 2026/04/13UR - https://scipost.org/SciPostPhysCore.9.2.022JF - SciPost Physics CoreJA - SciPost Phys. CoreVL - 9IS - 2SP - 022A1 - Jurčiukonis, DariusAU - Lavoura, LuísAB - We consider the extension of the Standard electroweak Model through an $SU(2)$ quadruplet of scalars with hypercharge either $3/2$ or $1/2$ (with an additional reflection symmetry in the latter case). We establish, through exact analytical equations, the boundaries of the phase spaces of the gauge-invariant terms that appear in the (renormalizable) scalar potentials. We devise procedures for the determination of necessary and sufficient bounded-from-below conditions on those potentials; we emphasize that one mostly needs to scan the scalar potential over a few lines, instead of surfaces, in order to establish the boundedness-from-below; this fact allows one to reduce by three orders of magnitude the computational time devoted to that establishment.ER - × @Article{10.21468/SciPostPhysCore.9.2.022, title={{On the addition of an SU(2) quadruplet of scalars to the Standard Model}}, author={Darius Jurčiukonis and Luís Lavoura}, journal={SciPost Phys. Core}, volume={9}, pages={022}, year={2026}, publisher={SciPost}, doi={10.21468/SciPostPhysCore.9.2.022}, url={https://scipost.org/10.21468/SciPostPhysCore.9.2.022},} Supplementary Information External links to supplemental resources; opens in a new tab. Code repository Authors / Affiliations: mappings to Contributors and Organizations See all Organizations. 1 Darius Jurčiukonis, 2 3 4 Luís Lavoura 1 Vilniaus universitetas / Vilnius University 2 Universidade de Lisboa / University of Lisbon 3 Instituto Superior Técnico / Instituto Superior Técnico [IST] 4 Centro de Física Teórica de Partículas / Centro de Física Teórica de Partículas [CFTP] Funders for the research work leading to this publication Fundação para a Ciência e a Tecnologia (through Organization: Fundação para a Ciência e Tecnologia [FCT]) NextGenerationEU Research Council of Lithuania / Lietuvos Mokslo Taryba