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1. Top-quark production at approximate N3LO

   https://doi.org/10.22323/1.398.0465  

   Kidonakis, Nikolaos (April 2022, The European Physical Society Conference on High Energy Physics (EPS-HEP2021))

   I discuss recent theoretical results with soft-gluon corrections for various top-quark production processes through approximate N3LO, including soft anomalous dimensions through three loops. I present numerical results for total cross sections and differential distributions for top-pair and tW production as well as for three-particle final states with a top quark and a Higgs boson. I show that soft-gluon corrections are dominant for a large range of collider energies. 

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2. Soft Anomalous Dimensions and Resummation in QCD

   https://doi.org/10.3390/universe6100165  

   Kidonakis, Nikolaos (October 2020, Universe)

   null (Ed.)

   I discuss and review soft anomalous dimensions in QCD that describe soft-gluon threshold resummation for a wide range of hard-scattering processes. The factorization properties of the cross section in moment space and renormalization-group evolution are implemented to derive a general form for differential resummed cross sections. Detailed expressions are given for the soft anomalous dimensions at one, two, and three loops, including some new results, for a large number of partonic processes involving top quarks, electroweak bosons, Higgs bosons, and other particles in the standard model and beyond. 

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3. Total and Differential Cross Sections for Higgs and Top-Quark Production

   https://doi.org/10.3390/universe4110121  

   Kidonakis, Nikolaos (November 2018, Universe)

   I present theoretical calculations for Higgs-boson and top-quark production, including high-order soft-gluon corrections. I discuss charged-Higgs production in association with a top quark or a W boson, as well as single-top and top-antitop production. Total cross sections as well as transverse-momentum and rapidity distributions of the top quark or the Higgs boson are presented for various LHC energies. 

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4. Three-loop effective potential for softly broken supersymmetry

   https://doi.org/10.1103/PhysRevD.109.015019  

   Martin, Stephen P (January 2024, Physical Review D)

   The effective potential has been previously calculated through three-loop order, in Landau gauge, for a general renormalizable theory using dimensional regularization. However, dimensional regularization is not appropriate for softly broken supersymmetric gauge theories, because it explicitly violates supersymmetry. In this paper, I obtain the three-loop effective potential using a supersymmetric regulator based on dimensional reduction. Checks follow from the vanishing of the effective potential in examples with supersymmetric vacua, and from renormalization scale invariance in examples for which supersymmetry is broken, either spontaneously or explicitly by soft terms. As byproducts, I obtain the three-loop Landau gauge anomalous dimension for the scalar component of a chiral supermultiplet, and the beta function for the field-independent vacuum energy. 

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5. Hybrid symmetry class topological insulators

   https://doi.org/10.21468/SciPostPhys.18.6.209  

   Das, Sanjib Kumar; Roy, Bitan (January 2025, SciPost Physics)

   Traditional topological materials belong to different Altland-Zirnbauer symmetry classes (AZSCs) depending on their non-spatial symmetries. Here we introduce the notion of hybrid symmetry class topological insulators (HSCTIs): A fusion of two different AZSC topological insulators (TIs) such that they occupy orthogonal Cartesian hyperplanes and their universal massive Dirac Hamiltonian mutually anticommute, a mathematical procedure we name hybridization. The boundaries of HSCTIs can also harbor TIs, typically affiliated with an AZSC that is different from the ones for the parent two TIs. As such, a fusion or hybridization between planar class AII quantum spin Hall and vertical class BDI Su-Schrieffer-Heeger insulators gives birth to a three-dimensional class A HSCTI, accommodating quantum anomalous Hall insulators (class A) of opposite Chern numbers and quantized Hall conductivity of opposite signs on the top and bottom surfaces. Such a response is shown to be stable against weak disorder. We extend this construction to encompass crystalline HSCTI and topological superconductors (featuring half-quantized thermal Hall conductivity of opposite sings on the top and bottom surfaces), and beyond three spatial dimensions. Non-trivial responses of three-dimensional HSCTIs to crystal defects (namely edge dislocations) in terms of mid-gap bound states at zero energy around its core only on the top and bottom surfaces are presented. Possible (meta)material platforms to harness and engineer HSCTIs are discussed. 

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