Related papers: Cosmology: theory
A primary goal of present and future colliders is measuring the Higgs couplings to Standard Model (SM) particles. Any observed deviation from the SM predictions for these couplings is a sign of new physics whose energy scale can be bounded…
We classify weak-scale extensions of the Standard Model which automatically preserve its accidental and approximate symmetry structure at the renormalizable level and which are hence invisible to low-energy indirect probes. By requiring the…
Results are reported from a search for non-standard-model Higgs boson decays to pairs of new light bosons, each of which decays into the oppositely charged dimuon final state. The new bosons may be produced either promptly or via a decay…
Nobody knows exactly what kind of Higgs physics will be unveiled when the Large Hadron Collider is turned on. There could be one Standard Model Higgs boson or five Higgs bosons as is the case in two-Higgs-doublet models; there could be more…
One of the simplest extensions of the Standard Model (SM) consists in adding a scalar singlet. This second Higgs boson is able to solve several fundamental problems of SM. Additional scalar particles arise naturally in composite Higgs…
We study a simple effective field theory incorporating six heavy vector bosons together with the standard-model field content. The new particles preserve custodial symmetry as well as an approximate left-right parity symmetry. The enhanced…
The presence of a bosonic resonance near 125 GeV has been firmly established at the Large Hadron Collider. Understanding the exact nature of this boson is a priority. The task now is to verify whether the boson is indeed the scalar Higgs as…
The search for the a Standard Model Higgs boson at the LHC is reaching a critical stage as the possible mass range for the particle has become extremely narrow and some signal at a mass of about 125 GeV is starting to emerge. We study the…
In this note we propose an overview on the current theoretical and experimental limits on a Higgs singlet extension of the Standard Model. We assume that the Boson which has recently been measured by the LHC experiments is the lightest…
The last particle that completes the Standard Model of Elementary Particles, the most sophisticated theory of nature in human history, was discovered in 2012. Although the present formulation of the theory comes from the 1960s and 70s, it…
The absence of low energy supersymmetry in run I data at the LHC has pushed the nominal scale for supersymmetry beyond a TeV. While this is consistent with the discovery of the Higgs boson at \approx 125 GeV, simple models with scalar and…
We consider a model based on the supersymmetric QCD theory with N_c=2 and N_f=3. The theory is strongly coupled at the infrared scale \Lambda_H. Its low energy effective theory below \Lambda_H is described by the supersymmetric standard…
We outline a new explanation for the primordial density perturbations in cosmology. Dimension zero fields are a minimal addition to the Standard Model of particle physics: if the Higgs doublet is emergent, they cancel the vacuum energy and…
In the motivated hypothesis that the scalar bosons of the Next-to-Minimal Supersymmetric Standard Model (NMSSM) be the lightest new particles around, a possible strategy to search for signs of the extra CP-even states is outlined. It is…
In the Standard Model, all massive elementary particles acquire their masses by coupling to a background Higgs field with a non-zero vacuum expectation value. What is often overlooked is that each massive particle is also a source of the…
The properties of the Higgs boson, h(125), observed in LHC data are consistent with Standard Model predictions. Consequently, if additional Higgs bosons are present, then the direction of h(125) in field space must be approximately aligned…
The apparent absence of new heavy states at the LHC below the TeV scale points that there is a gap in the electroweak energy spectrum. This scenario is conveniently described through the electroweak effective theory, an effective…
The current description of fundamental interactions is based on two theories with the status of standard models. The electromagnetic and nuclear interactions are described at a quantum level by the Standard Model of particle physics, using…
We study Higgs boson properties in a model where three fermionic families of the Standard Model arise from a single generation in (5+1) dimensions. We demonstrate that, in spite of a non-trivial background, properties of the…
The discovery of the Higgs boson by the ATLAS and CMS experiments concluded a glorious century of experimental particle physics discoveries, from Rutherford's discovery of the nucleus in 1911, through the discoveries of quarks and leptons…