|
Showing 1 - 5 of
5 matches in All Departments
Several of the very foundations of the cosmological standard model
the baryon asymmetry of the universe, dark matter, and the origin
of the hot big bang itself still call for an explanation from the
perspective of fundamental physics. This workadvocates one
intriguing possibility for a consistent cosmology that fills in the
theoretical gaps while being fully in accordance with the
observational data. At very high energies, the universe might have
been in a false vacuum state that preserved B-L, the difference
between the baryon number B and the lepton number L as a local
symmetry. In this state, the universe experienced a stage of hybrid
inflation that only ended when the false vacuum became unstable and
decayed, in the course of a waterfall transition, into a phase with
spontaneously broken B-L symmetry. This B-L Phase Transition was
accompanied by tachyonic preheating that transferred almost the
entire energy of the false vacuum into a gas of B-L Higgs bosons,
which in turn decayed into heavy Majorana neutrinos. Eventually,
these neutrinos decayed into massless radiation, thereby producing
the entropy of the hot big bang, generating the baryon asymmetry of
the universe via the leptogenesis mechanism and setting the stage
for the production of dark matter. Next to a variety of conceptual
novelties and phenomenological predictions, the main achievement of
the thesis is hence the fascinating notion that the leading role in
the first act of our universe might have actually been played by
neutrinos.
"
Several of the very foundations of the cosmological standard model
— the baryon asymmetry of the universe, dark matter, and the
origin of the hot big bang itself — still call for an explanation
from the perspective of fundamental physics. This
work advocates one intriguing possibility for a consistent
cosmology that fills in the theoretical gaps while being fully in
accordance with the observational data. At very high energies, the
universe might have been in a false vacuum state that preserved
B-L, the difference between the baryon number B and the lepton
number L as a local symmetry. In this state, the universe
experienced a stage of hybrid inflation that only ended when the
false vacuum became unstable and decayed, in the course of a
waterfall transition, into a phase with spontaneously broken B-L
symmetry. This B-L Phase Transition was accompanied by tachyonic
preheating that transferred almost the entire energy of the false
vacuum into a gas of B-L Higgs bosons, which in turn decayed into
heavy Majorana neutrinos. Eventually, these neutrinos decayed into
massless radiation, thereby producing the entropy of the hot big
bang, generating the baryon asymmetry of the universe via the
leptogenesis mechanism and setting the stage for the production of
dark matter. Next to a variety of conceptual novelties and
phenomenological predictions, the main achievement of the thesis is
hence the fascinating notion that the leading role in the first act
of our universe might have actually been played by neutrinos.
|
|