The European Physical Journal C

Abstract We develop a thermodynamic formulation of Cotton gravity in the Codazzi parametrization, providing a general framework in which the gravitational dynamics can be interpreted in terms of horizon thermodynamics. As paradigmatic examples, we apply the formalism to Friedmann–Robertson–Walker (FRW) and static spherically symmetric spacetimes. By implementing the first law of thermodynamics on…

Abstract We investigate Maxwell–Chern–Simons theory on a three-dimensional noncommutative spacetime endowed with a constant Poisson structure. By exploiting the residual rotational symmetry, we construct exact classical solutions corresponding to pointlike electric and magnetic charges. We demonstrate that noncommutativity acts as a natural regulator, ensuring a finite total electromagnetic energ…

Abstract In this work, we analyze the strong vertices of hadronic molecules DK , $$D^*K$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msup> <mml:mi>D</mml:mi> <mml:mo>∗</mml:mo> </mml:msup> <mml:mi>K</mml:mi> </mml:mrow> </mml:math> , $$DK^*$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>D</mml:mi> <mml:msup> <mml:mi>K</mml:mi> <mml:mo…

Abstract We study the nonlinear photon dynamics in quantum improved rotating black hole surrounded by perfect fluid dark matter (PFDM) using several methods of analysis, including Poincaré sections, Lyapunov exponents, Kolmogorov–Sinai (KS) entropy and weighted Birkhoff averages (WBA). In particular, we examine the effect of quantum-improved parameter $$(\tilde{\omega })$$ <mml:math xmlns:mml="ht…

Abstract We perform a model-independent investigation of the thermodynamic evolution of the Universe by reconstructing the expansion history from observational data using Gaussian Process regression. We consider three independent combinations of datasets, namely CC32+DESI DR2+Pantheon+, CC32+DESI DR2+Union3, and CC32+DESI DR2+DES Y5, allowing us to assess the impact of different supernova samples…

Abstract In this work, we construct spherically symmetric solutions of Bardeen–boson stars within the framework of the Einstein–Klein–Gordon theory coupled to nonlinear electrodynamics (NLED) by employing numerical methods. Considering a thin accretion disk in the equatorial plane as the light source, we systematically investigate the optical appearance of boson stars using the ray-tracing method…

<title>Abstract</title> A flagship application of quantum computers is the simulation of other quantum systems, including quantum field theories. In this article, we show how quantum computers can be employed to naturally calculate Feynman diagrams and their interferences in Quantum Chromodynamics (QCD). We simulate the colour parts of the interactions directly on the quantum computer, while the …

Abstract We construct charged black hole solutions in bumblebee gravity coupled to a general class of nonlinear electrodynamics (NLED) using an auxiliary Maxwell-scalar formalism. The norm-fixed radial configuration of the bumblebee vector makes the solutions asymptotic to a conical Lorentz-violating vacuum and requires stringent nonminimal bumblebee-NLED couplings. The general black hole solutio…

Abstract In this work, we derive the general solutions for a cylindrically symmetric space-time filled with a cosmological perfect fluid obeying $$p=\gamma \rho $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>p</mml:mi> <mml:mo>=</mml:mo> <mml:mi>γ</mml:mi> <mml:mi>ρ</mml:mi> </mml:mrow> </mml:math> ( $$0\le \gamma \le 1$$ <mml:math xmlns:mml="http://www.w3.org/199…

Abstract The KNO-violating term $$f_s$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>f</mml:mi> <mml:mi>s</mml:mi> </mml:msub> </mml:math> of the charged-particle multiplicity distribution in pp collisions measures the relative deviation of $$\langle n\rangle P_n$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mrow> <mml:mo>⟨</mml:mo> <m…

Abstract In the present work we explore for the first time the general structure and properties of the nonperturbative quark-gluon vertex in the complex plane. Specifically, we focus on the transversely-projected quark-gluon vertex that emerges from a recently developed symmetry-preserving approach for the study of meson properties beyond the rainbow-ladder approximation. The analysis focuses on …

Abstract The Real Higgs Triplet model, known as the $$\varDelta $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Δ</mml:mi> </mml:math> SM, is a minimal extension of the Standard Model (SM) obtained by adding a hypercharge 0 triplet ( $$\varDelta $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>Δ</mml:mi> </mml:math> ). This simple model is motivated by the…

Abstract Understanding the internal structure of the proton – including its mass spectrum, electromagnetic and gravitational form factors, and mechanical properties – remains a central challenge in hadronic physics. While lattice QCD and experimental measurements provide valuable insights, a holographic framework with a single parameter set capable of simultaneously describing these diverse obser…

Abstract A measurement of correction factors for the hadronic jet energy scale and resolution in the ATLAS detector is presented. These correction factors account for differences between simulated and observed data. They are obtained by analysing a selection of top quark events collected in proton–proton collisions by ATLAS between the years 2015 and 2018 at a centre-of-mass energy $$\sqrt{s} = 1…

Abstract We investigate the optical appearance of a Kerr–Bertotti–Robinson (Kerr-BR) black hole illuminated by a geometrically and optically thin accretion disk. Instead of using a phenomenological power-law emissivity, we adopt a magnetically driven synchrotron emissivity proxy coupled to the local electromagnetic environment. With a backward ray-tracing framework, we examine the effects of the …

Abstract The presence of $$\alpha $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>α</mml:mi> </mml:math> clustered structures in light nuclei can enhance the initial spatial anisotropies in relativistic nuclear collisions relative to those arising from nuclei with uniform density distributions. Thus, observables that are strongly sensitive to the initial geometry can be a mor…

Abstract We develop a covariant Hamiltonian formalism in which evolution is measured along the proper-time flow of an observer congruence, replacing the external coordinate-time derivative with the Lie derivative. Our formalism keeps the Hamiltonian split between evolution and configuration variables and expresses it through spacetime tensors projected relative to the chosen congruence. After qua…

Abstract Traditional diagnostics of black hole phase transitions rely on thermodynamic quantities defined at the event horizon or asymptotic boundary. Here, we demonstrate that the near-singularity geometry offers a sharp, independent probe of both first-order phase transitions and supercritical crossover. For scalarized AdS black holes exhibiting a first-order phase transition, the Kasner expone…

Abstract We discuss the reconstruction of scalar field potential necessary to witness inflation at the very early phase of the Universe. A minimally coupled inflaton field is considered along with a modified teleparallel gravity where the action contains a function of torsion. Reconstruction mechanism in a most general way is discussed. Constant roll inflation is imposed upon the field equations …

Abstract In this study, we investigate the polarized images of non-topological soliton Bardeen boson stars by solving the coupled Einstein nonlinear electrodynamics complex scalar field equations, based on the thin accretion disk model surrounding these compact objects. We focus on the influence of key parameters, including the initial scalar field, magnetic charge, observer inclination angle, an…