Related Experiment Video
Updated: Jun 3, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Stable charged cosmic strings
1Physics Department, Stellenbosch University, Matieland 7602, South Africa.
Abstract:
We study the quantum stabilization of a cosmic string by a heavy fermion doublet in a reduced version of the standard model. We show that charged strings, obtained by populating fermionic bound state levels, become stable if the electroweak bosons are coupled to a fermion that is less than twice as heavy as the top quark. This result suggests that extraordinarily large fermion masses or unrealistic couplings are not required to bind a cosmic string in the standard model. Numerically we find the most favorable string profile to be a simple trough in the Higgs vacuum expectation value of radius ≈10(-18) m. The vacuum remains stable in our model, because neutral strings are not energetically favored.
Related Concept Videos
Potential Due to a Polarized Object
Oscillations about an Equilibrium Position
First Law: Particles in Two-dimensional Equilibrium
Newton's first law tells us about the...
Sources and Properties of Electric Charge
Most atoms additionally constitute another fundamental particle, the neutron. It carries no electrical charge. A...
Nuclear Stability
To hold positively charged protons together in the...
Magnetic Field due to Moving Charges
Consider a point charge moving with a constant velocity. Like the electric field, the magnetic field at any point is directly proportional to the magnitude of the charge and inversely proportional to the square of the distance between the source point and the field point. However, unlike the electric field, the magnetic field is always perpendicular to the plane containing the line...

