809 research outputs found
Enhanced Higgs boson production and avoidance of CP-violation and FCNC in the MPP inspired 2HDM
The multiple point principle (MPP) can be used to suppress non--diagonal
flavour transitions and CP violation in the two Higgs doublet extension of the
standard model. We discuss the quasi--fixed point scenario in the MPP inspired
two Higgs doublet model which leads to the enhanced production of Higgs
particles at the LHC if the MPP scale is low.Comment: Talk given at the 2007 Europhysics Conference on High Energy Physics,
Manchester, England, 19-25 July 2007, CERN preprint number added, references
update
The Hierarchy Problem and an Exotic Bound State
The Multiple Point Principle, according to which there exist many vacuum
states with the same energy density, is put forward as a fine-tuning mechanism.
By assuming the existence of three degenerate vacua, we derive the hierarchical
ratio between the fundamental (Planck) and electroweak scales in the Standard
Model. In one of these phases, 6 top quarks and 6 anti-top quarks bind so
strongly by Higgs exchange as to become tachyonic and form a condensate. The
third degenerate vacuum is taken to have a Higgs field expectation value of the
order of the fundamental scale.Comment: 12 pages, 2 figures, to be published in the Proceedings of the 10th
International Symposium on Particles, Strings and Cosmology (PASCOS04),
Boston, 16-22 August 200
Crypto-baryonic Dark Matter
It is proposed that dark matter could consist of compressed collections of
atoms (or metallic matter) encapsulated into, for example, 20 cm big pieces of
a different phase. The idea is based on the assumption that there exists at
least one other phase of the vacuum degenerate with the usual one. Apart from
the degeneracy of the phases we only assume Standard Model physics. The other
phase has a Higgs VEV appreciably smaller than in the usual electroweak vacuum.
The balls making up the dark matter are very difficult to observe directly, but
inside dense stars may expand eating up the star and cause huge explosions
(gamma ray bursts). The ratio of dark matter to ordinary baryonic matter is
expressed as a ratio of nuclear binding energies and predicted to be about 5.Comment: 9 pages. Published version with shorter abstract and new referenc
Smallness of the cosmological constant and the multiple point principle
In this talk we argue that the breakdown of global symmetries in no--scale
supergravity (SUGRA), which ensures the vanishing of the vacuum energy density
near the physical vacuum, leads to a natural realisation of the multiple point
principle (MPP). In the MPP inspired SUGRA models the cosmological constant is
naturally tiny.Comment: Talk given at the 2007 Europhysics Conference on High Energy Physics,
Manchester, England, 19-25 July 2007, CERN preprint number added, references
update
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