Related papers: Mirror World at the Large Hadron Collider
Motivated by recent results from the LHC experiments, we analyze Higgs couplings in two Higgs doublet models with an approximate PQ symmetry. Models of this kind can naturally accommodate sizable modifications to Higgs decay patterns while…
Recently, conceptually new physics beyond the Standard Model has been proposed, where a hidden conformal sector provides ``unparticle'' which couples to the Standard Model sector through higher dimensional operators in low energy effective…
The Standard Model Higgs suffers from the hierarchy problem, typically implying new states within the reach of the LHC. If the Higgs is very heavy (~500 GeV) the states that cutoff the quadratic divergence may be beyond the reach of the…
We construct a simple theory in which the fine-tuning of the standard model is significantly reduced. Radiative corrections to the quadratic part of the scalar potential are constrained to be symmetric under a global U(4) x U(4)' symmetry…
We consider a hidden sector dark matter, where a singlet fermion is a cold dark matter and a real singlet scalar boson $S$ is a messenger between the SM and the hidden sectors. This singlet scalar will mix with the SM Higgs boson $h$, and…
We describe a novel variation of the mirror Twin Higgs model in which the color gauge group in both sectors is extended to SU(4$)_c$ and spontaneously broken to SU(3$)_c$ exclusively in the visible sector. Through this process, the mirror…
The existence of mirror fermions interacting strongly under a new gauge group and having masses near the electroweak scale has been recently proposed as a viable alternative to the standard-model Higgs mechanism. The main purpose of this…
The fundamental nature of dark matter is entirely unknown. A compelling candidate is Twin Higgs mirror matter, invisible hidden-sector cousins of the Standard Model particles and forces. This predicts mirror neutron stars made entirely of…
Depending on the Higgs-boson and top-quark masses, $M_H$ and $M_t$, the effective potential of the {\bf Standard Model} can develop a non-standard minimum for values of the field much larger than the weak scale. In those cases the standard…
The mirror twin Higgs model is a candidate for (strongly-interacting) complex dark matter, which mirrors SM interactions with heavier quark masses. A consequence of this model are mirror neutron stars -- exotic stars made entirely of mirror…
We consider scenarios of Higgs compositeness where the Higgs doublet arises as a pseudo-Nambu Goldstone boson. Our focus is the physical scalar ("radial") excitation associated with the global symmetry breaking vacuum, which we call the…
We discuss the connection between the vacuum energy problem and the number of dark matter sectors and its relation to the cancellation of quadratic divergences both in the cosmological constant and simultaneously in the polarization tensor…
A simple way to accommodate dark matter is to postulate the existence of a hidden sector. That is, a set of new particles and forces interacting with the known particles predominantly via gravity. In general this leads to a large set of…
The W-boson mass measurement recently reported by the CDF II experiment exhibits a significant deviation from both the Standard Model prediction and previous measurements. There is also a long-standing deviation between the Standard Model…
The Higgs discovery has given us the Higgs-gauge sector as a new handle to search for physics beyond the Standard Model. This includes physics scenarios originally linked to massive gauge boson scattering at high energies. We investigate…
It has recently been pointed out that the mirror or twin Higgs model is more technically natural than the standard model, thus alleviating the ``little'' hierarchy problem. In this paper we generalise the analysis to models with an…
A broad class of models in which electroweak symmetry breaking originates from dynamics in a singlet dark sector, and is transferred to the Standard Model via the Higgs portal, predicts in general strongly suppressed Higgs boson mixing with…
The recent measurement of the Higgs boson mass implies a relatively slow rise of the Standard Model Higgs potential at large scales, and a possible second minimum at even larger scales. Consequently, the Higgs field may develop a large…
We present `twin Higgs models', simple realizations of the Higgs as a pseudo-Goldstone boson that protect the weak scale from radiative corrections up to scales of order 5 - 10 TeV. In the ultra-violet these theories have a discrete…
We extend the standard model fermions by a mirror copy to realize a left-right symmetry. During a strongly first order phase transition of the spontaneous left-right symmetry breaking, the CP-violating reflections of the mirror fermions off…