Electroweak monopoles with a non-linearly realized weak hypercharge

AbstractWe present a finite-energy electroweak-monopole solution obtained by considering non-linear extensions of the hypercharge sector of the Electroweak Theory, based on logarithmic and exponential versions of electrodynamics. We find constraints for a class of non-linear extensions and also work out an estimate for the monopole mass in this scenario. We finally derive a lower bound for the energy of the monopole and discuss the simpler case of a Dirac magnetic charge.

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On finite energy monopole solutions in Weinberg–Salam model

International Journal of Modern Physics A ◽

10.1142/s0217751x1550164x ◽

2015 ◽

Vol 30 (27) ◽

pp. 1550164 ◽

Cited By ~ 3

Author(s):

D. G. Pak ◽

P. M. Zhang ◽

L. P. Zou

Keyword(s):

Magnetic Field ◽

Magnetic Charge ◽

Helical Structure ◽

Finite Energy ◽

Explicit Construction ◽

Axially Symmetric ◽

Gauge Invariant ◽

Monopole Solution ◽

Energy Formula ◽

Invariant Definition

We study the problem of existence of finite energy monopole solutions in the Weinberg–Salam model starting with the most general ansatz for static axially-symmetric electroweak magnetic fields. The ansatz includes an explicit construction of field configurations with various topologies described by the monopole and Hopf charges. We introduce a unique [Formula: see text] gauge invariant definition for the electromagnetic field. It has been proved that the magnetic charge of any finite energy monopole solution must be screened at far distance. This implies nonexistence of finite energy monopole solutions with a nonzero total magnetic charge. In the case of a special axially-symmetric Dashen–Hasslacher–Neveu ansatz, we revise the structure of the sphaleron solution and show that sphaleron represents a nontrivial system of monopole and antimonopole with their centers located in one point. This is different from the known interpretation of the sphaleron as a monopole–antimonopole pair like Nambu’s “dumb-bell.” In general, the axially-symmetric magnetic field may admit a helical structure. We conjecture that such a solution exists and estimate an upper bound for its energy, [Formula: see text].

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Accidental Gauge Symmetries of Minkowski Spacetime in Teleparallel Theories

Universe ◽

10.3390/universe7050143 ◽

2021 ◽

Vol 7 (5) ◽

pp. 143

Author(s):

Jose Beltrán Jiménez ◽

Tomi S. Koivisto

Keyword(s):

General Relativity ◽

Minkowski Spacetime ◽

Linear Extensions ◽

Gauge Symmetries ◽

Linear Spectrum ◽

Massless Spin ◽

Non Linear ◽

Common Framework ◽

Local Symmetries ◽

Quadratic Action

In this paper, we provide a general framework for the construction of the Einstein frame within non-linear extensions of the teleparallel equivalents of General Relativity. These include the metric teleparallel and the symmetric teleparallel, but also the general teleparallel theories. We write the actions in a form where we separate the Einstein–Hilbert term, the conformal mode due to the non-linear nature of the theories (which is analogous to the extra degree of freedom in f(R) theories), and the sector that manifestly shows the dynamics arising from the breaking of local symmetries. This frame is then used to study the theories around the Minkowski background, and we show how all the non-linear extensions share the same quadratic action around Minkowski. As a matter of fact, we find that the gauge symmetries that are lost by going to the non-linear generalisations of the teleparallel General Relativity equivalents arise as accidental symmetries in the linear theory around Minkowski. Remarkably, we also find that the conformal mode can be absorbed into a Weyl rescaling of the metric at this order and, consequently, it disappears from the linear spectrum so only the usual massless spin 2 perturbation propagates. These findings unify in a common framework the known fact that no additional modes propagate on Minkowski backgrounds, and we can trace it back to the existence of accidental gauge symmetries of such a background.

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FINITE ENERGY ONE-HALF MONOPOLE SOLUTIONS

Modern Physics Letters A ◽

10.1142/s0217732312502331 ◽

2012 ◽

Vol 27 (40) ◽

pp. 1250233 ◽

Cited By ~ 5

Author(s):

ROSY TEH ◽

BAN-LOONG NG ◽

KHAI-MING WONG

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Magnetic Flux ◽

Topological Charge ◽

Magnetic Monopole ◽

Magnetic Charge ◽

Finite Energy ◽

Spatial Infinity ◽

Yang Mills ◽

The Magnetic Field

We present finite energy SU(2) Yang–Mills–Higgs particles of one-half topological charge. The magnetic fields of these solutions at spatial infinity correspond to the magnetic field of a positive one-half magnetic monopole at the origin and a semi-infinite Dirac string on one-half of the z-axis carrying a magnetic flux of [Formula: see text] going into the origin. Hence the net magnetic charge is zero. The gauge potentials are singular along one-half of the z-axis, elsewhere they are regular.

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