arXiv subjects

Y. M. Cho

Publications and source records attributed to Y. M. Cho.

At least 19 recordsLinked to original sources

arXiv2025

New Monopoles in Non-Abelian Gauge Theories

The monopoles play important roles in physics. In this work we discuss the new monopoles in non-Abelian gauge theories, the standard model, the Georgi-Glashow model, and QCD. The standard model has two totally different types of monopoles, the Cho-Maison type monopoles which have the weak boson dressing and the electromagnetically neutral magnetic monopoles (the naked one and the one with the W boson dressing) which carries the neutral magnetic charge $4\pi/\bae$. The Georgi-Glashow model has a new monopole, the Wu-Yang monopole which has the W boson dressing, in addition to the well known 'tHooft-Polyakov monopole. And QCD has a new monopole, the Wu-Yang monopole which has the chromon dressing. We show how to construct the new monopoles and clarify the origin of the topology of the new monopoles. The new monopoles could have deep implications not just in high energy physics but also in low energy physics.

hep-ph↗

arXiv2025

Neutral Magnetic Monopole in the Standard Model

The standard model has the electroweak monopole which has the magnetic charge $4\pi/e$, as a hybrid between the Dirac and 'tHooft-Polyakov monopoles. We argue that it may have new type of monopoles, in particular the neutral monopole (``the Z monopole") which is electromagnetically neutral but has the neutral magnetic charge $4\pi/\be$, where $\be$ is the neutral charge. The mass of the new monopole could be less than the Cho-Maison monopole, around 3.28 TeV. We show how to construct the neutral monopole and clarify the origin of the topology of the new monopole. We discuss the implications of the new monopoles in physics.

hep-ph↗

arXiv2025

Electroweak Monopole-Antimonopole Pair Production at LHC

The monopole production at LHC crucially depends on the monopole production mechanism. We show that, if the monopole production mechanism at LHC is the thermal fluctuation of the Higgs vacuum as the early universe did, it is practically impossible for LHC to produce the monopole, even with the future FCC energy upgrade. This is because the temperature of the p-p fireball is simply too low to produce the monopole. But if the monopole production mechanism is the Drell-Yan and/or Schwinger mechanism, the 14 TeV LHC could produce the monopole in the form of the monopolium of mass around 5,7 TeV even when the monopole mass becomes 11 TeV. Or, it could produce the monopole when the mass is less than 7 TeV. Our result tells that, if the monopole production mechanism at LHC becomes the thermal fluctuation, searching for the remnant monopoles produced in the early universe could be the only way to detect the electroweak monopole. We discuss the physical implications of our result.

hep-ph↗

arXiv2025

Non-Abelian Ginzburg-Landau Theory of Spin Triplet Superconductivity

We present an SU(2)xU(1) generalization of the Ginzburg-Landau theory of the spin triplet ferromagnetic superconductivity which could also describe the physics of the spin triplet magnon spintronics, where the SU(2) gauge interaction of the magnon plays the central role. The theory is made of the massive photon, massless neutral magnon, massive non-Abelian magnon, and the Higgs scalar field which represents the density of the Copper pair. It has the following characteristic features, the long range magnetic interaction mediated by the massless magnon, two types of conserved supercurrents (the ordinary charge current and the magnon spin current), and the non-Abelian Meissner effect generated by the spin current. It has two types of vortices, the quantized magnetic and spin vortices. Moreover, it has two types of monopoles, the monopole which has the ordinary magnetic charge and the one which has the spin magnetic charge. The theory is characterized by three scales. In addition to the correlation length fixed by the mass of the Higgs field it has two different mass scales, the one fixed by the mass of the photon and the other fixed by the mass of the off-diagonal magnon. We discuss the physical implications of the theory of the spin triplet superconductivity in condensed matter physics.

cond-mat.supr-con↗

arXiv2025

Two Types of Gluons in QCD: Re-interpretation of ALEPH and CMS Gluon Jet Data

The Abelian decomposition of QCD tells that there are two types of gluons in QCD, the color neutral neurons and colored chromons, which behave differently. This strongly implies that QCD has two types of gluon jets, the neuron jet and chromon jet. One quarter of the gluon jets is made of the neuron jets which have sharper jet radius and smaller particle multiplicity, while three quarters of them are made of chromon jets which have the broader jet radius and larger particle multiplicity. Moreover, the neuron jet has a distinct color flow which forms an ideal color dipole pattern, while the chromon jets have distorted dipole pattern. In this paper we provide five circumferential evidences of the existence of two types of gluon jets from the existing ALEPH and DELPHI data on $e \bar e \rightarrow Z \rightarrow b \bar b g$ decay and the CMS data on Pb-Pb heavy ion collision.

hep-ph↗

arXiv2025

Theory of Magnon Spintronics: Non-Abelian Gauge Theory of Electron Spintronics

Treating the electron as a charged spinon we propose a theory of magnon spintronics, a non-Abelian gauge theory of SU(2)xU(1), which could be viewed as an effective theory of electron spintronics. Just like QED the theory has the U(1) electromagnetic interaction, but the new ingredient is the non-Abelian SU(2) gauge interaction of the magnon with the spinon. A remarkable feature of the theory is the photon-magnon mixing, the mixing between the electromagnetic U(1) gauge boson and the diagonal part of the SU(2) magnon gauge boson. After the mixing we have the massless Abelian magnon and a massive photon, and the doubly charged massive off-diagonal non-Abelian magnons which induce the spin-flip interaction to the spinon. The theory is characterized by three scales. In addition to the correlation length fixed by the mass of the Higgs field it has two different penetration lengths, the one fixed by the mass of the photon which generates the well known Meissner effect and the other fixed by the mass of the off-diagonal magnons which generates the non-Abelian Meissner effect. The non-Abelian structure of the theory naturally accommodates new topological objects, the non-Abrikosov quantized magnonic vortex and non-Abelian magnonic monopole of the Cho-Maison type, as well as the well known Abrikosov vortex. We discuss the physical implications of the non-Abelian gauge theory of the magnon spintronics.

cond-mat.supr-con↗

arXiv2025

Non-Abelian Magnon Gauge Interactions in Condensed Matter Physics

We discuss three different but closely related theories which could describe varieties of condensed matters, in particular the frustrated magnetic materials and the multi-gap (ferro)magnetic superconductors with or without the photon-magnon mixing, where the genuine non-Abelian magnon gauge interaction plays the central role. The charactristic features of these theories are the existence of long range magnetic order and the spin-spin interaction described by the exchange of the messenger bosons, not by the instantaneous action at a distance. These theories could play important roles in our understanding of non-Abelian condensed matters and make the non-Abelian gauge interaction a main stream in the low energy physics. We discuss the physical implications of our results.

cond-mat.supr-con↗

arXiv2025

Restricted Gravity: Lagrangian Formalism and Explicit Solutions

It is well known that, making the Abelian projection of Einstein's theory one can obtain the restricted gravity which is simpler than Einstein's theory but describes the core dynamics of Einstein's gravity. In this paper we present the Lagrangian formalism of the restricted gravity which makes the restricted gravity a self consistent field theory by itself, independent of Einstein's theory. With this we present interesting solutions of the restricted gravity, in particular the gravitational cosmic string, the Bertotti-Robinson spacetime, the axisymmetric pp-wave, and the conformally flat waves with flat wavefront. Moreover, we show that in the restricted gravity the Rosen-Bondi gravitational plane wave could be described by two spin-one Maxwellian potentials. This could play important role in quantum gravity. We discuss the physical implications of the restricted gravity.

gr-qc↗

arXiv2024

Electroweak Primordial Magnetic Blackhole: Cosmic Production and Physical Implication

The electroweak monopole, when coupled to gravity, turns to the Reissner-Nordstrom type primordial magnetic blackhole whose mass is bounded below, with the lower bound $M_P \sqrt α$. This changes the overall picture of the monopole production mechanism in the early universe drastically and has deep implications in cosmolpgy. In particular, this enhances the possibility that the electroweak monopoles turned to the primordial magnetic blackholes could become the seed of stellar objects and galaxies, and account for the dark matter of the universe. Moreover, this tells that we have a new type of primordial blackhole different from the popular primordial blackhole in cosmology, the electroweak primordial magnetic blackhole based on a totally different production mechanism. We discuss the physical implications of the electroweak primordial magnetic blackhole.

hep-th↗

arXiv2024

MoEDAL search in the CMS beam pipe for magnetic monopoles produced via the Schwinger effect

We report on a search for magnetic monopoles (MMs) produced in ultraperipheral Pb--Pb collisions during Run-1 of the LHC. The beam pipe surrounding the interaction region of the CMS experiment was exposed to 184.07 \textmu b$^{-1}$ of Pb--Pb collisions at 2.76 TeV center-of-mass energy per collision in December 2011, before being removed in 2013. It was scanned by the MoEDAL experiment using a SQUID magnetometer to search for trapped MMs. No MM signal was observed. The two distinctive features of this search are the use of a trapping volume very close to the collision point and ultra-high magnetic fields generated during the heavy-ion run that could produce MMs via the Schwinger effect. These two advantages allowed setting the first reliable, world-leading mass limits on MMs with high magnetic charge. In particular, the established limits are the strongest available in the range between 2 and 45 Dirac units, excluding MMs with masses of up to 80 GeV at 95\% confidence level.

nucl-ex↗

arXiv2024

Has Telescope Array Discovered Electroweak Monopole?

We propose the ultra high energy cosmic ray recently detected by Telescope Array to be the electroweak monopole, and present theoretical arguments which support this. This strongly motivates the necessity for the ``cosmic" MoEDAL experiment which could back up our proposal. To confirm this we propose Telescope Array to measure the magnetic charge of the ultra high energy cosmic ray particles with SQUID.

hep-ph↗

arXiv2023

Non-Abelian Landau-Ginzburg Theory of Ferromagnetic Superconductivity and Photon-Spinon Mixing

We propose an effective theory of non-Abelian superconductivity, an SU(2)xU(1) extension of the Abelian Landau-Ginzburg theory, which could be viewed as an effective theory of ferromagnetic superconductivity made of spin-up and spin-down doublet Cooper pair. Just like the Abelian Landau-Ginzburg theory it has the U(1) electromagnetic interaction, but the new ingredient is the non-Abelian SU(2) gauge interaction between the spin doublet Cooper pair. A remarkable feature of the theory is the mixing between the photon and the diagonal part of the SU(2) gauge boson. After the mixing it has massless gauge boson (the massless non-Abelian spinon) and massive gauge boson (the massive photon), in addition to the massive off-diagonal gauge bosons (the massive non-Abelian spinons) which induces the spin-flip interaction between the spin up and down components of the Cooper pair. So, unlike the ordinary Landau-Ginzburg theory it has a long range interaction mediated by the massless non-Abelian spinon, which could be responsible for the long range magnetic order and spin waves observed in ferromagnetic superconductors. The theory is characterized by three scales. In addition to the correlation length fixed by the mass of the Higgs field it has two different penetration lengths, the one fixed by the mass of the photon (which generates the well known Meissner effect) and the other fixed by the mass of the off-diagonal spinons (which determines the scale of the spin flip interaction). The non-Abelian structure of the theory naturally accommodates new topological objects, the non-Abrikosov quantized spin vortex (as well as the well known Abrikosov vortex) and non-Abelian spin monopole. We discuss the physical implications of the non-Abelian Landau-Ginzburg theory.

cond-mat.supr-con↗

arXiv2023

Experimental Verification of Two types of Gluon Jets in QCD

The Abelian decomposition of QCD tells that there are two types of gluons, the color neutral neurons and colored chromons. We propose to confirm the Abelian decomposition testing the existence of two types of gluon jets experimentally. We predict that one quarter of the gluon jet is made of the neurons which has the color factor 3/4 and the sharpest jet radius and smallest charged particle multiplicity, while the three quarters of the gluon jet are made of the chromons with the color factor 9/4 which have the broadest jet radious (broader than the quark jet). Moreover, we argue that the neuron jet has a distinct color flow which forms an ideal color dipole, while the quark and chromon jets have distorted dipole pattern. To test the plausibility of this proposal we suggest to analyse the gluon distribution against the jet shape (the sphericity) and/or particle multiplicity from the existing gluon jet events and look for two distinct peaks in the distribution.

hep-ph↗

arXiv2022

Search for Highly-Ionizing Particles in pp Collisions at the LHC's Run-1 Using the Prototype MoEDAL Detector

A search for highly electrically charged objects (HECOs) and magnetic monopoles is presented using 2.2 fb-1 of p - p collision data taken at a centre of mass energy (ECM) of 8 TeV by the MoEDAL detector during LHC's Run-1. The data were collected using MoEDAL's prototype Nuclear Track Detector array and the Trapping Detector array. The results are interpreted in terms of Drell-Yan pair production of stable HECO and monopole pairs with three spin hypotheses (0, 1/2 and 1). The search provides constraints on the direct production of magnetic monopoles carrying one to four Dirac magnetic charges (4gD) and with mass limits ranging from 590 GeV/c^2 to 1 TeV/c^2. Additionally, mass limits are placed on HECOs with charge in the range 10e to 180e, where e is the charge of an electron, for masses between 30 GeV/c^2 and 1 TeV/c^2.

hep-ex↗

arXiv2022

First experimental search for production of magnetic monopoles via the Schwinger mechanism

Schwinger showed that electrically-charged particles can be produced in a strong electric field by quantum tunnelling through the Coulomb barrier. By electromagnetic duality, if magnetic monopoles (MMs) exist, they would be produced by the same mechanism in a sufficiently strong magnetic field. Unique advantages of the Schwinger mechanism are that its rate can be calculated using semiclassical techniques without relying on perturbation theory, and the finite MM size and strong MM-photon coupling are expected to enhance their production. Pb-Pb heavy-ion collisions at the LHC produce the strongest known magnetic fields in the current Universe, and this article presents the first search for MM production by the Schwinger mechanism. It was conducted by the MoEDAL experiment during the 5.02 TeV/nucleon heavy-ion run at the LHC in November 2018, during which the MoEDAL trapping detectors (MMTs) were exposed to 0.235 nb$^{-1}$ of Pb-Pb collisions. The MMTs were scanned for the presence of magnetic charge using a SQUID magnetometer. MMs with Dirac charges 1$g_D$ $\leq$ $g$ $\leq$ 3$g_D$ and masses up to 75 GeV/c$^2$ were excluded by the analysis. This provides the first lower mass limit for finite-size MMs from a collider search and significantly extends previous mass bounds.

hep-ex↗

arXiv2021

First search for dyons with the full MoEDAL trapping detector in 13 TeV pp collisions

The MoEDAL trapping detector, consists of approximately 800 kg of aluminium volumes. It was exposed during Run-2 of the LHC program to 6.46 fb^-1 of 13 TeV proton-proton collisions at the LHCb interaction point. Evidence for dyons (particles with electric and magnetic charge) captured in the trapping detector was sought by passing the aluminium volumes comprising the detector through a SQUID magnetometer. The presence of a trapped dyon would be signalled by a persistent current induced in the SQUID magnetometer. On the basis of a Drell-Yan production model, we exclude dyons with a magnetic charge ranging up to 5 Dirac charges, and an electric charge up to 200 times the fundamental electric charge for mass limits in the range 790 - 3130 GeV.

hep-ex↗

arXiv2020

Abelian and Non-Abelian Monopole Configuration in Condensed Matters

We discuss the Abelian and non-Abelian monopoles which could exist in condensed matters. We show how the Dirac monopole can be regularized by the charge screening, and argue that the Dirac monopole of mass of hundred meVs could exist in dielectric condensed matters. Moreover, we generalize this result to non-Abelian condensed matters to show the existence of the non-Abelian monopole configuration in two-gap condensed matters, and present explicit monopole solutions.

hep-th↗

arXiv2020

Regularization of Electroweak Monopole by Charge Screening and BPS Energy Bound

We show that the electroweak monopole can be regularized with a non-vacuum electromagnetic permittivity. This allows us to set a new BPS bound for the monopole mass, which implies that the mass may not be smaller than 2.98 TeV, more probably 3.75 TeV. We demonstrate that the same method can also regularize the Dirac monopole, which enhances the possibility to construct the Dirac monopole of mass of a few hundred meV in condensed matters. We discuss the physical implications of our result.

hep-th↗