Related papers: Naturalness Under Stress
The discovery of the Higgs boson has put considerable pressure on theories that aim to solve the hierarchy problem. Scenarios in which the Higgs is a pseudo Nambu-Goldstone boson (NGB) of some new strong dynamics must possess a number of…
Little Higgs theories are an exciting new possibility for physics at TeV energies. In the Standard Model the Higgs mass suffers from an instability under radiative corrections. This ``hierarchy problem'' motivates much of current physics…
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…
The Standard Model of particle physics has a number of asymmetries suggestive of a more fundamental theory, where the symmetries are restored. If the symmetry breaking scale is the electroweak scale, new Higgs bosons beyond that of the…
In this talk, I shall address two key issues related to electroweak symmetry breaking. First, how fine-tuned different models are that trigger this phenomenon? Second, even if a light Higgs boson exists, does it have to be necessarily…
The discovery of the Higgs particle at around 126 GeV has given us a big hint towards the origin of the Higgs potential. The running quartic self-coupling decreases and crosses zero somewhere in the very high energy scale. It is usually…
Prospective searches about Higgs physics and beyond the Standard Model are presented for the CMS and ATLAS experiments. Possible excesses of events in real data could be an indication of the existence of new particles, even with few hundred…
If the minimal supersymmetric standard model is the solution to the hierarchy problem, the scalar top quark (stop) and the Higgsino should weigh around the electroweak scale such as 200 GeV. A low messenger scale, which results in a light…
Diverse experimental constraints now motivate models of supersymmetry breaking in which some superpartners have masses well above the weak scale. Three alternatives are focus point supersymmetry and inverted hierarchy models, which embody a…
At the Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN), protons and heavy ions are accelerated to velocities close to the speed of light and collided in order to study particle interactions and give us…
Today, both particle physics and cosmology are described by few parameter Standard Models, i.e. it is possible to deduce consequence of particle physics in cosmology and vice verse. The former is examined in this lecture, in light of the…
The discovery of the Higgs boson at the LHC has opened the door to clarify the mechanism of electroweak symmetry breaking and the origin of masses of particles. The Higgs sector in the SM is the simplest but has no theoretical principle, so…
The situation in particle physics after the discovery of the Higgs boson is discussed. Is the Standard Model complete? Are there still mysteries which have no answer? Answering these questions we consider the Higgs sector, the neutrino…
The fact that no evidence of new physics was found so far by LHC experiments has led some to call for the abandonment of the naturalness criterion. Others, on the contrary, have felt the need to break a lance in its defense by claiming that…
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…
The rather precise knowledge of the mass of the Higgs boson and of its couplings has important consequences for the physical phenomena taking place at the Fermi scale. We analyze some of these implications in the most motivated frameworks…
We study the naturalness problem using a model independent bottom up approach by considering models where only the interaction terms needed to cancel the Higgs quadratic divergences are present. If quadratic divergences are canceled by…
Even though the unified theory of electroweak interactions is very successful at low energies, there remains one part to be confirmed. It is the sector involving Higgs particles. Those Higgs particles are expected to be discovered. It has…
Discovering the dynamics responsible for electroweak symmetry breaking is the outstanding question facing particle physics today, and the answer will be found in the next decade. In these lectures I discuss the range of models which have…
Low energy supersymmetry is motivated by its use as a solution to the hierarchy problem of the electroweak scale. Having motivated this model with naturalness arguments, it is then necessary to check whether the experimentally allowed…