Post on 21-Feb-2016
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We shall find the answer in experiments at the LHC?
Most likely it will tells us a lot about the physics beyond the SM
SU(2)xSU(2) global symmetry of V :
Properties of the Higgs potential crucial forthe electroweak theory:
Spontaneously broken to the diagonal subgroup SU(2)
The Higgs mechanism then ensures that the Goldstone bosons become the longitudinal modes of the gauge bosons W,Z which acquire masses.
Renormalizability not crucial for EWSB
But crucial for ensuring unitarity of e.g. WW scattering by exchange of one physical Higgs particle h
INDEED,
In the Standard Model, the EWSB is described butnot explained
Can we better understand the Fermi scale? e.g. calculate it in terms of some more fundamental parameters?
The hierarchy problem of the Standard Model.
Fermi scale calculated in terms of the soft supersymmetry breaking parameters; generated by quantum corrections to the Higgs potential due to the large top quark mass(Ibanez, Ross)
The lightest physical scalar has similarproperties as the Higgs particle in the SM;
DOUBLE PROTECTION FOR THE HIGGS POTENTIAL
SUPERSYMMETRY PLUS LOW ENERGY GLOBAL SYMMETRY;
NO STRONGLY INTERACTING NEW PHYSICS
Non –supersymmetric „solutions” to the origin of the Fermi scale.
Revival of those approaches inspired by various theoreticalideas (extra dimensions, AdS/CFT correspondence, deconstruction,…
General picture –new strong interactions that provide a low-scale cut-off to the (non-renormalisable) electroweak theory and are responsible forelectroweak symmetry breaking
Barrel organ: the power source is commonly assumed to be a crank, turned by the operator or by his monkey.
A barrel organ player has been asked how to compose good music.
Just smoothly turn the crank, he replied.
CONCLUSION
Supersymmetry – elementary scalars
Minimal supersymmetric model – renormlizable extension of the SM
UV behaviour improved due to fermion-boson cancellations;
Superpartner masses- cut off in the SMHiggs potential
The impact of physics beyond the Standard Model on precision electroweak data can be studied in a modelindependent way by adding to the SM lagrangian higher dimension operators
In the Standard Model(with a Higgs particle –renormalizable theory) from the fits to LEP data we get