Speaker
Description
It is an unnatural feature of the Standard Model that the
difference between the baryon number B and the lepton number L
is conserved, which implies an exact, global symmetry.
We turn it into a naturally exact, local symmetry by coupling
the quantum number B-L to an Abelian gauge field.
Gauge anomalies are cancelled by adding right-handed neutrinos
nu_R, which are not sterile.
This forbids the Majorana term, but we arrange for a
nu_R-mass by adding a Higgs-type 1-component complex scalar
field. Thus we arrive at a modest but well-motivated
Standard Model extension.
We investigate the field equations in the corresponding extended
gauge-Higgs sector, involving both Higgs fields and the non-standard
U(1) gauge field. This leads to a set of coupled, non-linear
differential equations, which we solve numerically, focusing on
the structures of cosmic strings. For a large variety of parameters,
we identify the string profiles and energy densities.
These profiles depend on the winding number of each of the Higgs
fields. As an amazing peculiarity, we discover - for high winding
numbers - "overshooting" and "co-axial" solutions; in the latter
case, the profile of the standard Higgs field changes its sign
near the core of the cosmic string.
| I read the instructions above | Yes |
|---|