Related papers: Hidden Higgs Particle
The significance of the electroweak phase transition is undeniable, and although initially it was believed that it was second-order, it is now believed that it is a first-order transition. However, it is not a strong first-order phase…
The recent announcement of a discovery of a possible Higgs-like particle -its spin and parity is yet to be determined- at the LHC with a mass of 126 GeV necessitates a fresh look at the nature of the electroweak symmetry breaking, in…
We examine the fine-tuning associated to electroweak breaking in Little Higgs scenarios and find it to be always substantial and, generically, much higher than suggested by the rough estimates usually made. This is due to implicit tunings…
We define a set of pseudo-observables characterizing the properties of Higgs decays in generic extensions of the Standard Model with no new particles below the Higgs mass. The pseudo-observables can be determined from experimental data,…
The electroweak symmetry may be broken by a composite Higgs which arises naturally as a bound state of the top quark if the standard model gauge fields and fermions propagate in extra dimenions. The top quark mass and the Higgs mass can be…
I discuss the question whether it is possible that the LHC will find no signal for the Higgs particle. It is argued that in this case singlet scalars should be present that could play an important role in astroparticle physics. A critical…
Detection of a signal in one of the standard LHC Higgs search channels does not guarantee that the particle discovered is the Standard Model (SM) Higgs. In this talk I survey some general classes of alternatives and ways to tell them apart.
We propose a phenomenological solution to the Electroweak hierarchy problem. It predicts no new particles beyond those in the Standard Model. The Higgs is arbitrarily massive and slow-roll inflation can be implemented naturally. Loop…
The recent discovery at the LHC by the CMS and ATLAS collaborations of the Higgs boson presents, at long last, direct probes of the mechanism for electroweak symmetry breaking. While it is clear from the observations that the new particle…
We explore signals of new physics with two Higgs bosons and large missing transverse energy at the LHC. Such a signature is characteristic of models for dark matter or other secluded particles that couple to the standard model through an…
We present a version of the twin Higgs mechanism with minimal symmetry structure and particle content. The model is built upon a composite Higgs theory with global $SO(6)/SO(5)$ symmetry breaking. The leading contribution to the Higgs…
Although the Higgs particle is at the centre-stage of the Standard Model of particle physics and in many other related models, it has not been experimentally found so far. One of the major objectives of the Large Hadron Collider experiments…
Scenarios in which the Higgs vacuum arises radiatively and is separated from the origin by a potential barrier at zero temperature are known to be attainable in models with extra singlet scalars, which in the limit of zero barrier height…
The discovery of the Standard Model Higgs boson opens up a range of speculative cosmological scenarios, from the formation of structure in the early universe immediately after the big bang, to relics from the electroweak phase transition…
1. Why we do Believe in the Standard Model 2. Why we do not Believe in the Standard Model 2.1 Conceptual Problems 2.2 Hints from Experiment 2.2.1 Unification of Couplings 2.2.2 Dark Matter 2.2.3 Neutrino Masses 2.2.4 Baryogenesis 3. Status…
A discrete symmetry between quarks and (generalized) leptons can exist in nature, and its spontaneous symmetry breaking scale can be as low as a few TeV. Such a discrete symmetry also has interesting implications for how electroweak…
After the discovery of the Higgs boson and the rather precise measurement of all electroweak boson's masses the local structure of the electroweak symmetry breaking potential is already quite well established. However, despite being a key…
We present a model wherein the Higgs mass is protected from the quadratic one-loop top quark corrections by scalar particles that are complete singlets under the Standard Model (SM) gauge group. While bearing some similarity to Folded…
To investigate the possible effects of a light hidden sector on Higgs boson detection, we discuss a model of scalar singlets coupled to the Standard Model. The model effectively makes the Higgs width a free parameter due to additional…
Supersymmetric Twin Higgs models have a discrete symmetry for which each Standard Model particle and its supersymmetric partner have a corresponding state that transforms under a mirror Standard Model gauge group. This framework is able to…