Related papers: Supersimplicity: a remarkable high energy SUSY pro…
We derive a compact expression for the three-point MHV form factors of half-BPS operators in N=4 super Yang-Mills at two loops. The main tools of our calculation are generalised unitarity applied at the form factor level, and the compact…
Supersymmetric GUTs are the most natural extension of the Standard model unifying electroweak and strong forces. Despite their indubitable virtues, among these the gauge coupling unification and the quantization of the electric charge, one…
Recent LHC data, together with the electroweak naturalness argument, suggest that the top squarks may be significantly lighter than the other sfermions. We present supersymmetric models in which such a split spectrum is obtained through…
In the framework of the Constrained Minimal Supersymmetric Standard Model (CMSSM) we evaluate the electroweak fine tuning measure that provides a quantitative test of supersymmetry as a solution to the hierarchy problem. Taking account of…
Weak scale supersymmetry (SUSY) is highly motivated in that it provides a 't Hooft technically natural solution to the gauge hierarchy problem. However, recent strong limits from superparticle searches at LHC Run 2 may exacerbate a…
Though the one-loop amplitudes of the Higgs boson to massless gauge bosons are finite because there is no direct interaction at tree-level in the Standard Model, a well-defined regularization scheme is still required for their correct…
(Abridged) We report on a complete study of the single top-quark production by direct supersymmetric flavor-changing neutral-current (FCNC) processes at the LHC. The total cross section for pp(gg)->t\bar{c}+\bar{t}c is computed at the…
In this work we employ the MHV technique to show that scattering amplitudes with any number of consecutive soft particles behave universally in the multi-soft limit in which all particles go soft simultaneously. After identifying the…
We summarize methods and expected accuracies in determining the basic low-energy SUSY parameters from experiments at future e$^+$e$^-$ linear colliders in the TeV energy range, combined with results from LHC. In a second step we demonstrate…
The Standard Model contributions to the processes $\gamma \gamma \to \gamma \gamma$, $\gamma Z$ and ZZ at sufficiently high energies, are found to be helicity conserving and almost purely imaginary. This is due to the W-loop contribution,…
Low-energy SUSY and several other theories that address the hierarchy problem predict pair-production at the LHC of particles with Standard Model quantum numbers that decay to jets, missing energy, and possibly leptons. If an excess of such…
We analyze a set of three PT-symmetric complex potentials, namely harmonic oscillator, generalized Poschl-Teller and Scarf II, all of which reveal a double series of energy levels along with the corresponding superpotential. Inspired by the…
Second order supersymmetry transformations which involve a pair of complex conjugate factorization energies and lead to real non-singular potentials are analyzed. The generation of complex potentials with real spectra is also studied. The…
If Supersymmetry would manifest itself at a low mass scale it might be found already in the early phase of the LHC operation. Generic signatures for Supersymmetry in pp-collisions consist of high jet multiplicity, large missing transverse…
A study of the colour-ordered one-loop amplitudes in N=4 SYM reveals a surprising property: numerically, the amplitudes have an Approximately Universal form A^{1-loop}_n ~ A^{tree}_n \times U_n, where U_n is helicity independent. This form…
It is a remarkable fact that MHV amplitudes in maximally supersymmetric Yang-Mills theory at arbitrary loop order can be written as the product of the tree amplitude with the same helicity configuration and a universal, helicity-blind…
We rewrite various lattice Hamiltonian in condensed matter physics in terms of U(2/2) operators that we introduce. In this representation the symmetry structure of the models becomes clear. Especially, the Heisenberg, the supersymmetric t-J…
We present the complete one-loop matching of the Minimal Supersymmetric Standard Model (MSSM) onto the Standard Model Effective Field Theory (SMEFT), considering the most general case for the MSSM with conserved $R$-parity, which has 124…
At the LHC, many new physics signatures feature the pair-production of massive particles with subsequent direct or cascading decays to weakly-interacting particles, such as SUSY scenarios with conserved conserved R-parity or $H \to…
We analyze the effective 3 dimensional theory previously constructed for the MSSM and multi-Higgs models to determine the regions of parameter space in which the electroweak phase transition is sufficiently strong for a $B+L$ asymmetry to…