Frontiers in Physics 2025

25 Aug 2025, 05:00 → 29 Aug 2025, 13:00 Asia/Seoul

Centerpoint Gwanghwamun Building

The conference "Frontiers in Physics 2025" is a scientific conference focused on various topics at the cutting edge of the origin of the universe, such as particle physics, nuclear physics, and astrophysics.

The principal goal of the conference is to strengthen the growing communication between scientists working on the fundamental aspects of quantum chromodynamics, electroweak theory, quantum field theory, and their implications for quantum gravity and cosmology.

 

Frontiers in Physics 2025 Local Organizing Committee (FIP2025 LOC)
Yongmin Cho(SNU), Seung Hun Oh(Tech University of Korea), Sang-Woo Kim(Konkuk University), Hyojoong Kim(SNU)

Hosted by FIP2025 LOC
Organized by FIP2025 LOC, Natural Science Research Institute of University of Seoul, KSHEP(Korean Society of High Energy Physics)
Sponsored by APCTP(Asia Pacific Center of Theoretical Physics)

book_abstracts.pdf

fip2025-announcement-20250704.pdf

fip2025-poster.png

Monday 25 August

1 Registration

2 Opening

QCD

3 Two types of gluons in QCD: Experimental evidence

Two types of gluons in QCD: Experimental evidence

Speaker: Prof. Yongmin Cho (Seoul National University)

11:30 Break

QCD

4 Abelian Decomposition of QCD: Feynman Diagram Decomposition and Gluon Evolution Equations

This presentation synthesizes findings from studies on Abelian Decomposition of QCD Feynman Diagram, centered on the Cho-Duan-Ge theorem that splits gluons into color-neutral "neurons" and color-carrying "chromons". The work decomposes QCD Feynman diagrams for SU(2) and SU(3) gauge theories, deriving explicit rules for split vertices—including three-gluon, four-gluon, quark-gluon, and ghost-gluon interactions—that explicitly manifest color conservation. These rules, encompassing ghost fields, reveal hidden QCD structures obscured in conventional formulations.

Using time-ordered perturbation theory (TOPT), dynamical evolution equations for neurons and chromons are derived, consistent with traditional DGLAP equations as their combined contributions reproduce total gluon evolution. Numerical simulations show that in high $Q^2$ and small-$x$ region,, the chromon-to-neuron ratio stabilizes at 3:1 regardless of initial conditions. This framework enables refined analysis of gluon distributions in high-energy collisions, and two types of gluon distributions can be used as inputs for calculating cross-sections in high-energy collision processes.

Speaker: Yirui Yang (Peking University)

12:30 Lunch

QCD

5 Lattice study of quark confinement in view of the Cho-Duan-Ge decomposition method

The dual superconductivity picture is one of the most promising mechanisms for quark confinement. Since the proposal of Abelian projection by 't Hooft, evidence for the dual superconductivity picture has been demonstrated by lattice simulation. However, there have been theoretical concerns about the Abelian projection method, such as the breaking of gauge symmetry and color (global) symmetry, and that confinement is only observed in specific gauges, such as the MA gauge.
To overcome the problems of the Abelian projection method (of 't Hoof type) and clarify the confinement mechanism in a gauge-independent method, we transform the gauge-covariant decomposition method first proposed by Cho-Duan-Ge to lattice gauge theory, which enabled us to extract and examine the degrees of freedom contributing to confinement in a gauge-invariant way. This means the problems in the Abelian projection method have been settled in a gauge-independent manner.
In this talk, we will first briefly review the gauge-covariant decomposition method and its applications to study confinement mechanisms. In particular, we will explain applications to the confinement of quarks in the higher representations, for which the Abelian projection method could not provide a recipe to measure the string tension. If time permits, we will discuss applications to gauge-scalar models with the gauge-independent Brout-Englert-Higgs mechanism.

Speaker: Akihiro Shibata (Computing Research Center, KEK)

18:00 Banquet

Tuesday 26 August

Gravitation

6 Black hole solutions in Lorentz-violating gravity theories

In this talk, we report some exact solutions for static spherically symmetric black holes and rotating black holes in Lorentz-violating gravity theories with and without a cosmological constant. In these theories, Lorentz symmetry is spontaneously broken when a nonminimally coupled bumblebee vector field or Kalb-Ramond tensor field acquires a nonzero vacuum expectation value. The static spherically symmetric solutions describe the Reissner–Nordström-like black hole and Reissner–Nordström-(anti) de Sitter-like black hole, while the stationary and axially symmetric solutions describe the Kerr–Newman-like black hole and Kerr–Newman–(anti) de Sitter-like black hole. Building upon these solutions, we investigate black hole shadows the thermodynamic properties of the black holes.

Speaker: Prof. Yu-Xiao Liu (Lanzhou University)

7 f(T) thick brane and QNMs

Curvature, torsion and non-metricity are geometric trinity. F(T) theory modifies the metric teleparallel gravity. We constructed a thick brane model in f(T) theory. Tensor perturbations are analyzed and the localization of graviton zero mode is studied. Besides, we also studied the quasinormal modes of f(T) thick brane and gravitational echos can also be found.

Speaker: Wen-Di Guo

8 Emerging black hole shadow from collapsing boson star

In this work, we study the dynamical emergence of black hole shadows from gravitational lensings in a time-dependent spacetime generated by a collapsing boson star. Our results show that, as the boson star evolves, new Einstein rings continuously emerge from the lensing center. Their radii and number gradually increase until the formation of the light ring. Significantly, when the time delay is ignored, the black hole shadow with finite-size appears instantaneously at the moment of black hole formation. However, after taking into account the time delay of the light, shadow formation follows a more intricate process: it initially emerges as a minute dot at the lensing center, gradually expands as the black hole grows, and eventually extends into the inner region of the light ring. Furthermore, at the final stage of the collapsing boson star, the lensing and shadow structures with and without time delay remain nearly identical, indicating the elimination of the influence of time delay. Our findings reveal universal dynamical patterns in gravitational lensing and shadow formation, providing insights into potential observational signatures near the collapsing stars and the newborn black holes.

Speaker: Yu-Peng Zhang (Lanzhou University)

11:30 Break

Gravitation

9 GW observations and its impact on Neutron Star Equation of State

The observation of gravitational wave signal GW150914, generated by the merger of two black holes, marked the official beginning of gravitational wave observations and opened a new window on the universe. The fourth gravitational wave observation campaign (O4) is currently underway, with approximately two to three gravitational wave signal candidates being observed each week. By the end of the O3 observation campaign, 90 gravitational wave signals had been confirmed, and during the O4 period, 224 gravitational wave signal candidates were detected.
The observation of the gravitational wave signal GW170817, generated by the merger of two neutron stars, and the subsequent observation of its electromagnetic (EM) counterpart have ushered in a new era of multi-messenger astronomy.
In particular, GW170817 is a signal generated by the merger of a binary neutron star system and is an important observational result for neutron star research.
In this presentation, we will review the gravitational wave signals observed to date, explain the methods used to study the equation of state of neutron stars using gravitational wave signals generated by binary neutron star mergers, and discuss future expectations.

Speaker: Young-Min Kim (Korea Astronomy and Space Science Institute (KASI))

13:00 Lunch

Wednesday 27 August

Monopole

10 Detection of Cho-Maison monopole at LHC

Detection of Cho-Maison monopole at LHC

Speaker: Prof. Yongmin Cho (Seoul National University)

11 Monopole and string configurations in the standard model

We show the existence of the electroweak monopole string in the standard model. The string is made of monopole–antimonopole pair separated infinitely apart, which carry the quantized magnetic flux. We also show how to construct such quantized magnetic monopole and string solutions.

Speaker: Liping Zou

12 Vortex Particles: A New Perspective on Orbital Angular Momentum

Particles can carry not only spin but also orbital angular momentum (OAM), forming so-called “vortex” states. While these states have been studied in optics and electron microscopy, recent theoretical developments suggest that relativistic vortex particles could be created and manipulated in accelerator experiments. In this talk, I will give a brief overview of the concept of vortex particles and their intrinsic orbital angular momentum, highlighting potential connections to high-energy physics and fundamental interactions. The discussion is conceptual and intended to introduce this emerging topic to a broader QCD and gravity audience.

Speaker: Qi Meng (Sun Yat-Sen University)

11:30 Break

Monopole

13 The Monopole Quest: From Colliders to the Cosmos

Magnetic monopoles occupy a singular role in modern theoretical physics, emerging naturally in a wide array of frameworks—from Dirac’s quantization condition to Grand Unified Theories (GUTs), electroweak symmetry breaking, and candidate theories of quantum gravity. Their existence is often a topological necessity, associated with the non-trivial vacuum structure of gauge theories. As Joseph Polchinski famously observed: “The existence of magnetic monopoles seems to be one of the safest bets that one can make about physics beyond the Standard Model. Their properties can be studied in quantum field theory, and they are expected to exist in almost any extension of the Standard Model.”- J. Polchinski, “Monopoles, Duality, and String Theory”, Int. J. Mod. Phys. A 19S1, 145 (2004).

This talk surveys the status and prospects of monopole searches across the vast landscape of accessible energy scales—from the TeV regime of collider experiments to the Planck-scale physics potentially revealed through relics from the early universe. At colliders, experiments such as MoEDAL-MAPP, ATLAS, and CMS have targeted Dirac and electroweak monopoles using both Drell-Yan, photon-fusion and Schwinger production mechanisms. These searches confront the challenges of strong coupling and non-perturbative dynamics head-on.

At higher mass scales, inaccessible to collider production, the search continues via cosmic and astroparticle observatories. Experiments such as MACRO, SLIM, IceCube, ANITA, and LUX-ZEPLIN, as well as studies of ancient mica, seek to detect relic monopoles originating from early-universe symmetry breaking—possibly from inflationary reheating or first-order phase transitions. These searches span a broad range of monopole velocities and masses, with sensitivities guided by theoretical benchmarks such as the Parker bound and catalysis-induced proton decay cross sections. Unlike collider searches, these experiments probe fluxes that are motivated by cosmological and astrophysical considerations, independent of detailed collider-scale dynamics.

We shall see that the monopole is not merely a theoretical curiosity but a critical test of our most ambitious physical theories, as foundational as the Higgs boson in the architecture of fundamental physics.

Speaker: James Pinfold (University of Alberta (CA))

13:00 Lunch

Thursday 28 August

QCD

14 Huizhou Hadron Spectrometer (HHaS) in China

The HIAF facility in Guangdong, China, will provide high-intensity proton beams up to 9.3 GeV and heavy-ion beams—including uranium—up to 2.45 GeV/u. These capabilities will enable a wide spectrum of cutting-edge research, including the search for new particles and interactions beyond the Standard Model, tests of fundamental symmetries, the exploration of exotic hadron states, the investigation of di-baryons, and studies of non-perturbative QCD phenomena. To maximize scientific output, we plan to develop an advanced experimental spectrometer at the HIAF high-energy terminal, the Huizhou Hadron Spectrometer (HHaS). The successful construction and operation of HHaS will mark a significant milestone for medium- and high-energy particle and nuclear physics in China, opening new avenues for understanding the fundamental structure of matter.

Speakers: Xurong Chen, Xurong Chen

15 Investigation of Jet Structures Including Gluon Candidates in Three-Jet Events at LEP1

Three-jet events in (e^{+}e^{-}) collisions at (\sqrt{s} = 91.2)~GeV are reanalyzed using archived ALEPH data from LEP1 to study gluon-jet fragmentation. Unfolded observables are compared to Monte Carlo simulations. While quark-like jets show good agreement, gluon-like jets exhibit discrepancies, particularly in low-multiplicity and high-fragmentation regions. This is very preliminary result.

Speaker: Mr Youngkwon Jo (University of Seoul, Department of Physics (KR))

presentation_gluonJet_youngkwonjo_FIP2025_20250824.pdf

16 Studies of the quark-like and gluon-like contributions using jet charge measurements in heavy ion collisions with the CMS experiment

The main goal of relativistic heavy ion physics is to achieve a deep understanding of the quark-gluon plasma (QGP), a deconfined state of matter believed to have existed in the early universe.
One of the key probes of the QGP is jet quenching, which leads to a stronger suppression of gluon jets than quark jets.
This effect has been explained by many theoretical predictions and confirmed by continuous experimental results.
However, some experimental observations remain unexplained within the current understanding of jet physics, and jet charge measurement is one of the subject.
In this talk, jet charge measurements in PbPb collisions with the CMS experiment will be presented, with a focus on disentangling the quark-like and gluon-like contributions.
In addition, prospects for future heavy ion programs could be used for the potential studies will be introduced.

Speaker: Hyunchul Kim (Chonnam National University (KR))

11:30 Break

QCD

17 Possible exotic states in three-meson systems

In this talk, I will review some works on the studying of dynamically generated exotic states in three-meson systems.

Speaker: Dr Ju-Jun Xie (Institute of Modern Physics, Chinese Academy of Sciences)

13:00 Lunch

QCD SM

18 KCMS Activities

Friday 29 August

Other Frontiers

19 Fundamental Solutions of Restricted Gravity

It is well known that, by making the Abelian projection of Einstein's theory, one can obtain a restricted theory of gravity that is simpler than Einstein's theory but still describes the core dynamics of Einstein's gravity. In this talk, we present interesting solutions of restricted gravity, specifically the gravitational cosmic string, the Bertotti-Robinson spacetime, the axisymmetric pp-wave, and the conformally flat waves with wavefronts. Moreover, we demonstrate that in restricted gravity, gravitational plane waves can be described by two spin-one Maxwellian potentials. This could play an important role in quantum gravity. We discuss the physical implications of the restricted gravity.

Speaker: SEUNG HUN OH (Tech University of Korea)

20 Branes wrapped on spindles and discs

Branes wrapped on spindles and discs

Speaker: Hyojoong Kim

11:00 Break

Other Frontiers

21 Weinberg-Salam Theory as Theory of Magnon Electron Spintronics

Weinberg-Salam Theory as Theory of Magnon Electron Spintronics

Speaker: Yongmin Cho (Seoul National University)

22 Closing Remark