We investigate the generation of the matter–antimatter asymmetry in the early universe, prior to the electroweak phase transition, by extending the Standard Model with three right-handed neutrinos that complete Dirac mass terms and two heavy scalar fields. This constitutes a minimal and well-motivated Beyond-the-Standard-Model framework, since the Standard Model alone cannot account for neutrino masses or produce the observed baryon asymmetry due to insufficient CP violation. Using the Closed Time Path (CTP) formalism, we analyze-2-by 2 scattering processes mediated by heavy off-shell scalars. Since these scalars remain off-shell throughout, the post-inflationary temperature of the universe does not need to be high enough to produce them on-shell.

In this setup, right-handed neutrinos depart from thermal equilibrium, generating a lepton asymmetry that is subsequently converted into the observed baryon asymmetry via sphaleron processes. We compute the resulting baryon-to-photon ratio and compare it with the observational value reported by the Planck mission. We also compare the predicted contribution of the right-handed neutrinos to the effective number of relativistic species N_{eff}​ with current cosmological bounds, confirming the model’s consistency with observations.

The use of the CTP formalism eliminates the need for Real Intermediate State (RIS) subtraction, leading to a more consistent and elegant treatment. Furthermore, by incorporating quantum statistical factors, we demonstrate that viable asymmetry generation is achievable even with only two right-handed neutrino flavours. Consequently, the mechanism is generic and does not rely on specific particle species such as leptoquarks or other particular Standard Model extensions.

The 2012 landmark discovery of the Higgs boson by the ATLAS and CMS experiments marked the beginning of the new era for the LHC to precisely characterise this particle to validate and push the boundaries of the Standard Model through exploration at the highest available energies. To fully exploit the scientific potential of the LHC, both the accelerator and its detectors are undergoing extensive upgrades as part of the High-Luminosity LHC (HL-LHC) project, corresponding to an expected number of 140 to 200 simultaneous proton–proton interactions per bunch crossing by the end of the decade. A central element of this effort is the reinforcement of the forward muon system, for which CMS is deploying three new GEM-based muon stations: GE1/1, GE2/1, and ME0. These detectors combine excellent spatial resolution (∼250 μm), high-rate capability (>1 kHz/cm²), and radiation tolerance, while providing additional coordinate measurements and redundancy in combination with the existing Cathode Strip Chambers (CSCs) and RPCs. The GE1/1 station consists of 144 triple-GEM modules, arranged in super-chambers in both CMS endcaps, covering the range 1.55 < ∣η∣ < 2.18. The GE2/1 station, with 72 GEM chambers composed of 288 modules, extends coverage approximately over 1.62 < ∣η∣ < 2.43. The six-layer ME0 station, covering approximately 60 m², will be installed behind the new high-granularity calorimeter (HGCAL) during the third Long Shutdown (LS3) and will extend the CMS muon system’s pseudo-rapidity coverage from |η| < 2.4 to |η| < 2.8. Full system of GE1/1 and a few GE2/1 stations are contributing to the data taking in Run-3 with an operational efficiency above 95%. GEM technology efficiently rejects background and improves the precision of the muon bending angle measurement. This work presents an overview of the muon spectrometer upgrade of the CMS with GEM detectors, including operational experience and performance of the GEM station.

Testing the strong-field regime of gravity has become of great interest in the scientific community following the first gravitational wave detections and growing indications that General Relativity (GR) may require modifications in extreme environments.
In this context, black holes are remarkably simple yet powerful laboratories, providing a unique opportunity to search for deviations from GR and to constrain extensions of gravity in extreme conditions.
A natural framework to explore such deviations is through the inclusion of additional scalar degrees of freedom. Among them, scalar–Gauss–Bonnet (sGB) gravity offers a well-motivated framework, emerging naturally from fundamental high-energy theories such as string theory.
While most existing studies have focussed on massless versions of this theory, introducing a scalar field mass is crucial for a more realistic description and may uncover novel dynamical features.
Motivated by these considerations, I will present recent black hole simulations in massive sGB theory obtained using Numerical Relativity (NR), a rapidly expanding field that has only recently enabled fully non-linear, dynamical studies of compact objects beyond General Relativity and whose full potential is still being explored.
I will first focus on the role of the scalar mass in the spacetime dynamics, as well as the effects of massive scalar perturbations in isolated black holes in the context of quasinormal-mode spectroscopy.
Building on this groundwork, I will then introduce preliminary results from fully dynamical black hole merger simulations in massive sGB gravity, a regime that to date has seen only limited exploration and remains largely unexplored in the massive scalar case.

This work investigates the thermal deconfining phase transition from a hadronic gas composed of massive pions to a quark–gluon plasma (QGP) described by the Polyakov–Nambu–Jona-Lasinio (PNJL) model with two light quark flavors. The PNJL model extends the Nambu–Jona-Lasinio (NJL) approach, including chiral symmetry dynamics and the Polyakov loop, allowing a more realistic description of the QGP phase. A temperature-dependent switching function (SF) is used to ensure a smooth crossover between the hadronic and QGP phases. We analyze the temperature dependence of key thermodynamic quantities, including the pressure, energy density, entropy density, and the square of the speed of sound, and study the influence of pion and quark masses on the equation of state (EOS). This analysis provides a better understanding of the interplay between particle properties and the thermodynamic properties of the system, helping to provide a more comprehensive and accurate picture of the thermal behavior of hadronic matter at zero chemical potential, including its response to changes in temperature and energy. This is essential for interpreting heavy-ion collision results and simulating early-universe conditions. Our analysis results are systematically compared with available lattice QCD data, providing valuable insights and allowing us to assess the accuracy of the model and its ability to describe strongly interacting matter at high temperatures.

Experimental measurements of the large-scale anisotropy of Galactic cosmic rays (CRs) reveal a sharp change in the phase of the dipole component at energies around 100 TeV. Most traditional interpretations invoke macroscopic diffusion models of CR propagation or the influence of nearby sources; however, such approaches often do not adequately account for the local magnetic-field structure at the observer, which can substantially distort the measured anisotropy. Here we treat the anisotropy as a generic consequence of the local magnetic-field properties and the particle transport regime and therefore expect it to manifest at arbitrary locations in the Galaxy, rather than being specific to the vicinity of the Solar System. The source distribution and the local field parameters primarily determine the characteristic energy and the width of the dipole-phase transition region.

In this work, we model CR transport microscopically by numerically integrating particle trajectories in an interstellar magnetic field represented as the superposition of a uniform regular component and an isotropic turbulent component with a Kolmogorov spectrum. The turbulent field is generated using a harmonic method. The anisotropy is computed using the backtracking method to construct a sky map of the arrival intensity, followed by a multipole decomposition and extraction of the dipole term. We show that the sharp phase change is naturally associated with a crossover in the propagation regime. At energies where the Larmor radius is smaller than the turbulence correlation length, particles remain tied to local field lines and the dipole phase aligns with the local magnetic-field direction. Once the Larmor radius exceeds the correlation length, transport approaches standard three-dimensional diffusion, and the phase stabilizes along the direction set by the large-scale regular field. Our numerical results indicate that the position and the width of the phase-transition region are determined primarily by this transport-regime crossover.

Atomic nuclei are self-organized, many-body quantum systems bound by strong nuclear forces within femtometre-scale space. The shape and orientation of colliding nuclei play a crucial role in determining the initial conditions of the quark–gluon plasma (QGP), which influence key observables such as anisotropic and radial flow. In this talk, I will present an “imaging-by-smashing” approach using soft probes that are directly sensitive to the structure of colliding nuclei, from large to small systems, in high-energy nuclear collisions [1,2,3]. We present the measurements of , fluctuation, and − correlations in isobar-like²³⁸U+²³⁸U and ¹⁹⁷Au+¹⁹⁷Au collisions at 193 and 200 GeV, respectively. Our results reveal prominent differences in these observables between the two systems, particularly in the most central collisions. We also present the first measurements of in ¹⁶O+¹⁶O and d+¹⁹⁷Au collisions, providing insight into the impact of nucleon–nucleon correlations and further shedding light on the initial conditions of QGP droplets. Comparisons with the state-of-the-art hydrodynamic calculations enable us to extract the nuclear shape parameters across energy scales [4,5]. This interdisciplinary research enhances our understanding of the initial conditions in high-energy collisions and provides new insights into the evolution of nuclear structure across energy scales.

References:
[1] STAR Collaboration, Nature 635, 67-72 (2024)

[2] STAR Collaboration, Rep. Prog. Phys. 88, 108601 (2025)

[3] STAR Collaboration, arXiv:2510.19645

[4] C. Zhang, J. Jia, J. Chen, C. Shen, L. Liu, arXiv:2504.15245

[5] C. Zhang, J. Chen, G. Giacalone, S. Huang, J. Jia, Y.-G. Ma, PLB862, 139322(2025)

Schwarzschild solitons and Generalized Schwarzschild solitons have recently been studied on the new metrized smooth metric space of convex functions.

The completeness of geodesics and the Cauchy hypersurfaces are established for Schwarzschild spacetimes after correction [Hawking, S.W.: Commun. Math. Phys. 25, 152–166 (1972).].

The solitons are newly posed on the pseudo-spherical General Relativistic cylinder, with new equations set and uniquely solved.

The uniqueness of Schwarzschild solitons is newly investigated.

The concurrent vector field in General Relativity is newly defined, and the 4-position vector is newly indicated as a concurrent vector field in General Relativity; the Killing vector field is newly determined accordingly to the 4-velocity vector when the configuration of the observer frame is chosen as one solidal with the photon.

New isopoertimetric inequalities and new curvature estimates are provided to hold. New thoerems are proven about these geometries.

The Penrose tipping lightcones are newly written for these spacetimes; the cross-sections are determined accordingly. Accordingly, the Yamabe flow on the S2 sphere is newly proven to converge for submersion from a Schwarzschild spacetime: geodesics spheres are taken into account.

Submersions and immersions are newly discussed when these spacetimes are considered according to the pullback from the metric tensor.

The elements are also gathered for discussion of the Penrose 1965 Theorem.

We investigate finite-size effects on the density-driven deconfinement phase transition (DPT) in Quantum Chromodynamics (QCD) using a model of coexisting hadronic and quark–gluon plasma (QGP) phases in a finite volume. The QGP phase is modeled via the MIT bag approach, explicitly incorporating the color-singletness constraint to account for the color confinement. As a continuation of our previous work, in the present study, we will analyze the first and second chemical derivatives of the order parameter across a range of quark chemical potentials (μ), at fixed temperature (T) and for several volume (V) selections, to determine the effective transition point in a finite volume. Our results reveal that the effective transition chemical potential μ_c(V) shifts to higher values as the system size decreases, highlighting the pronounced influence of finite-volume effects. Moreover, the rapid variations in the order parameter and its chemical susceptibility at the transition in large volumes, are rounded off in small volumes, and the transition region is smeared out, acquiring a width δµ(V) which increases with decreasing volume. These findings provide a comprehensive understanding of how finite-volume constraints influence the QCD phase structure, offering important insights for interpreting results from heavy-ion collisions and other high-energy experiments where the system size is inherently limited.

General relativity (GR) lays the foundation for successfully explaining the current gravitational wave (GW) observations. We present a method for studying the orbital frequency evolution of GWs from binary black hole (BBH) systems based on their energy distribution on the time-frequency plane. The orbital frequency evolution of BBH systems is determined by the individual masses and spins of the component black holes and the governing gravity theory. If a beyond-GR theory of gravity governs the BBH orbital evolution for the same set of binary parameters, the time-frequency pixel energies will exhibit a different frequency evolution from what is predicted by GR. We develop a new consistency test to check whether GR explains the BBH orbital evolution. Through numerical simulation of beyond-GR theory of gravity, we demonstrate the efficiency of this new method in detecting any possible departure from GR in the framework of second-generation GW interferometers. Further, we discuss the utility of our method in probing missing physics in the GW waveform models. We apply our test to the GW190814 and GW190412 data from the LIGO-Livingston detector, assuming that the analyzing template waveform does not include higher-order modes. The lack of subdominant modes results in an incomplete representation of the GW signal, leading to systematic biases in the frequency evolution of the signal.

In this study, we investigated the Bianchi type-V model in the context of f(R, T) gravity.

Here, we have considered the f(R, T)=R+2f(T), where f(T)= λT where λ is an arbitrary constant, R is the Ricci scalar, and T is the trace of stress energy momentum tensor. We have made the assumption that the cosmic jerk parameter, j, is precisely proportional to the negative of the deceleration parameter, q, namely in order to solve the field equations. The conversation covers a variety of situations including the Hubble parameter (H), the spatial volume (V), the deceleration parameter (q), the energy density (ρ), the pressure of matter (p), and the cosmological constant (Λ). We investigate a bouncing point, the moment of transition between contraction to expansion. The value of the expansion scalar θ describes a smooth, bounded transition between contraction and expansion which represents a bouncing universe (avoiding Big Bang singularity) and also represents a bouncing universe with maximum expansion rate due to modified gravity. The model also diagnoses the de Sitter universe, where exponential expansion is driven by a cosmological constant or dark energy. The model looks at the physical and geometrical behavior of the model, as well as the exact solutions under the anticipated jerk parameter condition, and summarizes key findings.