Simple and Realistic Composite Higgs Models in Flat Extra Dimensions

We construct new composite Higgs/gauge-Higgs unification (GHU) models in flat space that overcome all the difficulties found in the past in attempting to construct models of this sort. The key ingredient is the introduction of large boundary kinetic terms for gauge (and fermion) fields. We focus our analysis on the electroweak symmetry breaking pattern and the electroweak precision tests and show how both are compatible with each other. Our models can be seen as effective TeV descriptions of analogue warped models. We point out that, as far as electroweak TeV scale physics is concerned, one can rely on simple and more flexible flat space models rather than considering their unavoidably more complicated warped space counterparts. The generic collider signatures of our models are essentially undistinguishable from those expected from composite Higgs/warped GHU models, namely a light Higgs, colored fermion resonances below the TeV scale and sizable deviations to the Higgs and top coupling.Comment: 30 figures, 9 figures; v2: minor improvements, one reference added, version to appear in JHE

Effective Action and Holography in 5D Gauge Theories

We apply the holographic method to 5D gauge theories on the warped interval. Our treatment includes the scalars associated with the fifth gauge field component, which appear as 4D Goldstone bosons in the holographic effective action. Applications are considered to two classes of models in which these scalars play an important role. In the Composite-Higgs (and/or Gauge-Higgs Unification) scenario, the scalars are interpreted as the Higgs field and we use the holographic recipe to compute its one-loop potential. In AdS/QCD models, the scalars are identified with the mesons and we compute holographically the Chiral Perturbation Theory Lagrangian up to p^4 order. We also discuss, using the holographic perspective, the effect of including a Chern-Simons term in the 5D gauge Lagrangian. We show that it makes a Wess-Zumino-Witten term to appear in the holographic effective action. This is immediately applied to AdS/QCD, where a Chern-Simons term is needed in order to mimic the Adler-Bardeen chiral anomaly.Comment: 37 pages; v2, minor changes, one reference added; v3, minor corrections, version published in JHE

L'intervento dello Stato a favore della crescita nel quadro delle regole dell'Unione europea

This paper focuses on the State intervention as a driver for a growth within the framework of the EU rules on State aid, especially with regard to local infrastructure investments. In particular, it aims to illustrate the approach (big on big things and small on small things) recently adopted by the European Commission, which is reinforcing its partnership with the Member States on the implementation of the new rules on State aid as they have now increased their responsibility to grant aid without prior notification to the Commission. This strengthened partnership should create conditions so that the Commission can support strategic investments of Member States, by working with them on how to design growth-enhancing aid measures that promote a strong, integrated and dynamic single market. Concerning the implementation of the assessment criteria of the compatibility of an aid, the Commission carries out a balancing test where the impact of the project on the common European interest could be decisive. From this perspective, more attention should be paid to aid measures having a local relevance. A change in the Commission attitude may be found in a set of decisions recently taken and concerning local public support measures that are unlikely to affect competition. What is needed is the research of a new balancing test between State intervention in favour of economic growth and development and protection of competition. This new method of assessment might start from local infrastructures and services

Le attività funerarie nel diritto europeo ed italiano : il nuovo disegno di legge di riforma

Il disegno di legge di riforma delle attivit\ue0 funerarie A.C n. 3189 del 22 giugno 2015, nel rispondere ad una esigenza largamente sentita di riordino e aggiornamento dell'attuale disciplina, introduce meccanismi di autorizzazione e di pianificazione territoriale che trovano giustificazione, per i servizi mortuari, nella loro natura pubblicistica e, per quelli di pompe funebri, nell'interesse generale a che essi siano prestati nel rispetto, in particolare, dei diritti dei dolenti. La distinzione fra i due ordini di servizi \ue8 stata fatta propria dalla Corte di giustizia che riconosce peraltro agli Stati un ampio margine di discrezionalit\ue0 nell'introduzione di possibili restrizioni alla loro libera prestazione, purch\ue9 siano rispettate al riguardo le condizioni poste dalla giurisprudenza della stessa Corte in tema di esercizio delle libert\ue0 fondamentali. Nel perseguire l'interesse generale le disposizioni contenute nel disegno di legge di riforma introducono limitazioni alla libert\ue0 di iniziativa economica che sia rispondono ai requisiti fissati dall'ordinamento comunitario sia risultano compatibili con le indicazioni fornite dalla AGCM

Improving Effective Surgical Delivery in Humanitarian Disasters: Lessons from Haiti

Kathryn Chu and colleagues describe the experiences of Médecins sans Frontières after the 2010 Haiti earthquake, and discuss how to improve delivery of surgery in humanitarian disasters

Weak Mixing Angle and Higgs Mass in Gauge-Higgs Unification Models with Brane Kinetic Terms

We show that the idea of Gauge-Higgs unification(GHU) can be rescued from the constraint of weak mixing angle by introducing localized brane kinetic terms in higher dimensional GHU models with bulk and simple gauge groups. We find that those terms lead to a ratio between Higgs and W boson masses, which is a little bit deviated from the one derived in the standard model. From numerical analysis, we find that the current lower bound on the Higgs mass tends to prefer to exceptional groups E(6), E(7), E(8) rather than other groups like SU(3l), SO(2n+1), G(2), and F(4) in 6-dimensional(D) GHU models irrespective of the compactification scales. For the compactification scale below 1 TeV, the Higgs masses in 6D GHU models with SU(3l), SO(2n+1), G(2), and F(4) groups are predicted to be less than the current lower bound unless a model parameter responsible for re-scaling SU(2) gauge coupling is taken to be unnaturally large enough. To see how the situation is changed in more higher dimensional GHU model, we take 7D S^{3}/ Z_{2} and 8D T^{4}/ Z_{2} models. It turns out from our numerical analysis that these higher dimensional GHU models with gauge groups except for E(6) can lead to the Higgs boson whose masses are predicted to be above the current lower bound only for the compatification scale above 1 TeV without taking unnaturally large value of the model parameter, whereas the Higgs masses in the GHU models with E(6) are compatible with the current lower bound even for the compatification scale below 1 TeV.Comment: 22 pages, 4 figure

Leptons in Holographic Composite Higgs Models with Non-Abelian Discrete Symmetries

We study leptons in holographic composite Higgs models, namely in models possibly admitting a weakly coupled description in terms of five-dimensional (5D) theories. We introduce two scenarios leading to Majorana or Dirac neutrinos, based on the non-abelian discrete group $S_4\times \Z_3$ which is responsible for nearly tri-bimaximal lepton mixing. The smallness of neutrino masses is naturally explained and normal/inverted mass ordering can be accommodated. We analyze two specific 5D gauge-Higgs unification models in warped space as concrete examples of our framework. Both models pass the current bounds on Lepton Flavour Violation (LFV) processes. We pay special attention to the effect of so called boundary kinetic terms that are the dominant source of LFV. The model with Majorana neutrinos is compatible with a Kaluza-Klein vector mass scale $m_{KK}\gtrsim 3.5$ TeV, which is roughly the lowest scale allowed by electroweak considerations. The model with Dirac neutrinos, although not considerably constrained by LFV processes and data on lepton mixing, suffers from a too large deviation of the neutrino coupling to the $Z$ boson from its Standard Model value, pushing $m_{KK}\gtrsim 10$ TeV.Comment: 37 pages, 4 figures; v2: Note added in light of recent T2K and MINOS results, figures updated with new limit from MEG, references added, various minor improvements, matches JHEP published versio

Anomalous Couplings in Double Higgs Production

The process of gluon-initiated double Higgs production is sensitive to non-linear interactions of the Higgs boson. In the context of the Standard Model, studies of this process focused on the extraction of the Higgs trilinear coupling. In a general parametrization of New Physics effects, however, an even more interesting interaction that can be tested through this channel is the (ttbar hh) coupling. This interaction vanishes in the Standard Model and is a genuine signature of theories in which the Higgs boson emerges from a strongly-interacting sector. In this paper we perform a model-independent estimate of the LHC potential to detect anomalous Higgs couplings in gluon-fusion double Higgs production. We find that while the sensitivity to the trilinear is poor, the perspectives of measuring the new (ttbar hh) coupling are rather promising.Comment: 22 pages, 9 figures. v2: plots of Figs.8 and 9 redone to include experimental uncertainty on the Higgs couplings, references adde