This study examines the validity of the Generalized Second Law of Thermodynamics (GSLT) to generalized Chaplygin gas (GCG) and modified Chaplygin gas (MCG) models within the general relativity(GR) framework and modified gravity framework namely the $\textit{f}$($\textit{T}$) gravity. Three distinct models of GCG and MCG are analyzed with bulk viscosity included in the GR framework to account for the dissipative process during cosmic evolution while the $\textit{f}$($\textit{T}$) gravity is considered without bulk viscosity. To study the thermodynamic implications of the model, our study employs three distinct forms of entropy: Tsallis, Barrow and Sharma–Mittal entropy. Furthermore, a highly generalized version of holographic cutoff has also been explored under the purview of the reconstruction approaches under consideration inspired by $\textit{The European Physical Journal C}$, 77:1–8. Our results confirm that the models satisfy the GSLT with total entropy change remaining positive thus confirming the thermodynamic stability of GCG and MCG and the robustness of these forms of entropy in describing the universe’s thermodynamic behaviour. Additionally, for the two Chaplygin gas models with bulk viscosity in the GR framework, the GSLT is validated and the results show the thermodynamical stability of these models with the inclusion of bulk viscosity term and interaction terms as well.

India

Khandro Chokyi

Surajit Chattopadhyay

Testing generalized second law of thermodynamics in cosmological models with bulk viscosity and modified gravity

This paper addresses a potential validation of the weak gravity conjecture (WGC) with the weak cosmic censorship conjecture (WCCC), as a significant challenge in quantum gravity. We explore the viability of the WGC and WCCC in the context of the Kerr-Newman-Kiselev-Letelier (KNKL) black hole. Although these conjectures appear unrelated, but surprising connection between these conjectures establishes a bridge between the quantum and the cosmic. By imposing specific constraints on the black hole's parameters, we demonstrate that the WGC and WCCC can be compatible in certain regions. We examine the properties of the KNKL black hole for <math altimg='si1.svg'><mi>q</mi><mo stretchy='false'>/</mo><mi>m</mi><mo linebreak='goodbreak' linebreakstyle='after'>&gt;</mo><msub><mrow><mo stretchy='false'>(</mo><mi>Q</mi><mo stretchy='false'>/</mo><mi>M</mi><mo stretchy='false'>)</mo></mrow><mrow><mi>e</mi><mi>x</mi><mi>t</mi></mrow></msub></math>, where <math altimg='si2.svg'><msub><mrow><mo stretchy='false'>(</mo><mi>Q</mi><mo stretchy='false'>/</mo><mi>M</mi><mo stretchy='false'>)</mo></mrow><mrow><mi>e</mi><mi>x</mi><mi>t</mi></mrow></msub></math> is the charge-to-mass ratio of a large extremal black hole. We present figures to test the validity of both conjectures simultaneously. Without the spin parameter <italic>a</italic>, the cloud of string parameter <italic>b</italic>, quintessence parameter <italic>&#947;</italic>, and equation of state parameter <italic>&#969;</italic>, the black hole either has two event horizons if <math altimg='si3.svg'><msup><mrow><mi>Q</mi></mrow><mrow><mn>2</mn></mrow></msup><mo stretchy='false'>/</mo><msup><mrow><mi>M</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>&#8804;</mo><mn>1</mn></math> or none event horizon if <math altimg='si4.svg'><msup><mrow><mi>Q</mi></mrow><mrow><mn>2</mn></mrow></msup><mo stretchy='false'>/</mo><msup><mrow><mi>M</mi></mrow><mrow><mn>2</mn></mrow></msup><mo linebreak='goodbreak' linebreakstyle='after'>&gt;</mo><mn>1</mn></math> which leads to a naked singularity that contradicts the WCCC. However, when <italic>a</italic>, <italic>b</italic>, <italic>&#947;</italic>, and <italic>&#969;</italic> are present, the black hole has event horizons in some regions in the <math altimg='si4.svg'><msup><mrow><mi>Q</mi></mrow><mrow><mn>2</mn></mrow></msup><mo stretchy='false'>/</mo><msup><mrow><mi>M</mi></mrow><mrow><mn>2</mn></mrow></msup><mo linebreak='goodbreak' linebreakstyle='after'>&gt;</mo><mn>1</mn></math> that ensure the singularity is covered and both the WGC and WCCC are fulfilled. Actually, we face this issue in the extremality state of the black hole viz these conjectures remain viable, with the black hole maintaining an event horizon. We conclude that certain regions of <italic>a</italic>, <italic>b</italic>, <italic>&#947;</italic>, and <italic>&#969;</italic> parameters can make the WGC and WCCC compatible, indicating their agreement when these parameters are present.

Iran

Saeed Noori Gashti

Azerbaijan

Behnam Pourhassan

Cosmic-quantum connections: Assessing the viability of weak gravity and weak cosmic censorship conjectures in Kerr-Newman-Kiselev-Letelier black hole

We investigate the <math altimg='si1.svg'><mi mathvariant='script'>N</mi><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><mn>2</mn></math> supersymmetric generalization of the dual equivalence between the Maxwell-Chern-Simons model and two massive self-dual models. One of the self-dual models is described by a real scalar superfield, while the other is described by a chiral spinor superfield. The equivalence is analyzed in the presence of dynamical matter chiral superfields. Initially, we establish the duality by demonstrating the existence of master actions that interpolate between the models. We then show that the field equations are identical when the proper identifications are made. Finally, we confirm the dual equivalence by defining a master generating functional, which, after changing the variables, provides the generating functionals of the Maxwell-Chern-Simons model and the two massive self-dual models coupled to matter.

Brazil

F.S. Gama

J.R. Nascimento

A.Yu. Petrov

P. Porfirio

Dual equivalence between the Maxwell-Chern-Simons theory and two self-dual massive models interacting with matter in <math altimg='si1.svg'><mi mathvariant='script'>N</mi><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><mn>2</mn></math>, <italic>d</italic>&#8239;=&#8239;3 superspace

Here we investigate a general class of massless local theories of spin 2 and spin 3, both invariant under generalized transverse diffeomorphisms (TDiff). We identify the ghost-free region in their parameter space and show the relationship of those models with the “doublet” action stemming from the tensionless limit of the open bosonic string field theory (for symmetric tensors). The connection is implemented via a nonlocal field redefinition which introduces a Stueckelberg-like field of rank 0 (rank 1) for the spin-2 (spin-3) case. An apparent mismatch between most TDiff models and the “doublet” action has led us to prove a nontrivial equivalence among TDiff models, thereby restoring consistency. Any point in the parameter subspace of ghost-free TDiff models is equivalent to any other one within that subspace. In particular, they are all physically equivalent to their simplest versions known as Maxwell-like models. So, the physical TDiff models seem to differ from each other by a Becchi-Rouet-Stora-Tyutin cohomologically trivial term.

R. Schimidt Bittencourt

D. Dalmazi

B. dos S. Martins

E.L. Mendonça

Equivalence of spin-2 and spin-3 models invariant under transverse diffeomorphisms and the tensionless limit of string theory

The inverse seesaw mechanism provides a concise scenario to produce tiny neutrino masses. Here we investigate the Majoron dark matter arising from the $$\mathrm{U(1)_L}$$ symmetry spontaneous breaking and matter–antimatter asymmetry in the framework of a high scale inverse seesaw mechanism. Due to the existence of a lepton-number-violating mass term, the Majoron gets its mass from radiative corrections. On the other hand, the Noether’s theorem indicates that the Majoron can obtain a non-zero initial velocity in the early universe, and then generates the relic abundance via kinetic misalignment mechanism. With the same initial Majoron velocity, the observed baryon asymmetry can also be explained through the so-called spontanous bayogenensis mechanism.

China

Ying-Quan Peng

Xiu-Fei Li

Cogenesis of Majoron dark matter and baryon asymmetry from a high scale inverse seesaw mechanism

We introduce the Higgs mechanism for the self-dual spin connection (also known as the Ashtekar connection), using the Plebański formulation of gravity. We develop our formalism within the framework of the chiral action and derive the equations of motion of the theory. One particular test model is explored: since anisotropy is an intrinsic property of the theory, a modified version of the spatially flat Bianchi I model with two different scale factors is considered. We apply our formalism and derive the Friedmann equations which regulate the scale factors and the Higgs field. We also present a Proca-like term for the connection, which when reduced to minisuperspace with a positive $$\Lambda $$ yields a De Sitter universe with an effective cosmological constant that depends on the mass of the gauge fields. We finally investigate the effect of these mass terms on gravitational waves and find that the wave equation remains unchanged relatively to GR; however the Weyl tensor is scaled by a constant which depends on the mass of the connection components.

United Kingdom

Bruno Alexandre

Higgs mechanism for the Ashtekar self-dual connection

The manifest disparity in Hawking radiation temperatures between black hole and cosmological horizons in de Sitter (dS) spacetime reveals a non-equilibrium thermal configuration, inherently violating thermodynamic stability criteria. This asymmetry poses significant challenges to the systematic analysis of dS thermodynamics. In this study, we construct a thermodynamic framework for dS spacetime under the condition that the system’s thermodynamic quantities adhere to the first law of thermodynamics, while enforcing thermal equilibrium between horizons through radiation temperature-equivalent conditions. Our ansatz postulates that spacetime entropy constitutes both horizon entropy contributions with a supplementary correction term. Through variational analysis constrained by equilibrium thermodynamics, we derive and solve thermodynamic constraints to obtain corrected entropy relations that explicitly resolve the two-horizon entropy puzzle for $\textit{n}$-dimensional charged dilaton-dS black holes. Utilizing these corrected entropy relations, we renormalize associated thermodynamic quantities, thereby establishing self-consistent extended thermodynamics. Numerical solutions of the Gibbs criteria reveal parameter-dependent critical points, where heat capacity is diverging signal possible second-order phase transitions. The system manifests phase transition phenomena, structurally homologous to liquid–gas transition in conventional thermodynamic systems. We proved that the system satisfies the conditions for equilibrium stability, allowing equilibrium phase transitions to occur near critical points.

Hui-Hua Zhao

Yun-Zhi Du

Yu-Bo Ma

Entropy correction and phase transition of $\textit{n}$-dimensional charged dilaton dS black holes

This study explores anisotropic Morris-Thorne-type wormhole models with <math altimg='si1.svg'><mi mathvariant='script'>D</mi></math>-dimensional Einstein gravity, focusing on various shape functions. We analyze the influence of the monopole parameter on the wormhole's throat and curvature through 2 <math altimg='si1.svg'><mi mathvariant='script'>D</mi></math> and 3 <math altimg='si1.svg'><mi mathvariant='script'>D</mi></math> embedding diagrams, showing that higher monopole values lead to wider throats and flatter geometries, enhancing stability and traversability. Energy conditions are examined for four wormhole models (M-I to M-IV), revealing that exotic matter is required near the throat. The anisotropy parameter is studied to assess internal force behavior, providing insight into the wormhole's structural stability. Additionally, the volume integral quantifier is employed to estimate the total amount of exotic matter, indicating that only a small quantity is needed to sustain traversable geometries. These findings offer theoretical insights into wormhole configurations in <math altimg='si1.svg'><mi mathvariant='script'>D</mi></math>-dimensional Einstein gravity and their relevance in extended gravitational frameworks.

Enhua Dai

Pakistan

M. Yousaf

Faisal Javed

Saudi Arabia

Mansour Shrahili

Rana Muhammad Zulqarnain

Imprints of monopole charge in Morris-Thorne type wormholes and energy conditions under the influence of higher dimensional gravity

The energy dependence of the cross section of the ( <italic>n,p</italic>) and ( <italic>n,d</italic>) reactions on natC has been studied for the first time at the n_TOF facility at CERN, from the particle detection threshold up to 25 MeV. The measurement was performed with two telescopes made of position-sensitive silicon &#916; <italic>E</italic>- <italic>E</italic> detectors, covering the angular range from 20 &#8728; to 140 &#8728;. A detector efficiency has been determined by means of Monte Carlo simulations of the experimental setup. Various assumptions on the angular distributions and branching ratios of the excited levels of the residual 11B, 12B, 13B nuclei were considered. In particular, theoretical calculations based on the TALYS-2.0 code were used and the systematic uncertainties in the analysis results were determined from the variations in these distributions. The n_TOF data on the ( <italic>n,p</italic>) and ( <italic>n,d</italic>) reaction on carbon are characterized by a higher accuracy and wider energy range than currently available in literature. A comparison with current evaluations from different libraries reveals a rather significant disagreement with the n_TOF results, while a remarkable agreement is observed with the prediction of TALYS-2.0 for this light element.

Croatia

P. Žugec

Italy

N. Colonna

Switzerland

D. Rochman

M. Barbagallo

Poland

J. Andrzejewski

J. Perkowski

A. Ventura

D. Bosnar

A. Gawlik-Ramięga

Spain

M. Sabaté-Gilarte

Austria

France

M. Bacak

F. Mingrone

E. Chiaveri

O. Aberle

V. Alcayne

S. Amaducci

L. Audouin

V. Babiano-Suarez

S. Bennett

E. Berthoumieux

J. Billowes

A. Brown

M. Busso

M. Caamaño

L. Caballero-Ontanaya

F. Calviño

M. Calviani

D. Cano-Ott

A. Casanovas

F. Cerutti

G. Cortés

M.A. Cortés-Giraldo

L. Cosentino

S. Cristallo

L.A. Damone

P.J. Davies

Greece

M. Diakaki

M. Dietz

C. Domingo-Pardo

R. Dressler

Germany

Q. Ducasse

E. Dupont

I. Durán

Z. Eleme

B. Fernández-Domínguez

A. Ferrari

P. Finocchiaro

V. Furman

K. Göbel

R. Garg

S. Gilardoni

Portugal

I.F. Gonçalves

E. González-Romero

C. Guerrero

F. Gunsing

Japan

H. Harada

S. Heinitz

Belgium

J. Heyse

D.G. Jenkins

A. Junghans

F. Käppeler

Y. Kadi

A. Kimura

Czechia

I. Knapová

M. Kokkoris

Y. Kopatch

M. Krtička

D. Kurtulgil

I. Ladarescu

C. Lederer-Woods

H. Leeb

J. Lerendegui-Marco

S.J. Lonsdale

D. Macina

A. Manna

T. Martínez

M. Martínez-Cañada

A. Masi

C. Massimi

P. Mastinu

M. Mastromarco

E.A. Maugeri

A. Mazzone

E. Mendoza

A. Mengoni

V. Michalopoulou

P.M. Milazzo

J. Moreno-Soto

A. Musumarra

Romania

A. Negret

R. Nolte

F. Ogállar

A. Oprea

N. Patronis

A. Pavlik

C. Petrone

L. Piersanti

E. Pirovano

I. Porras

J. Praena

Measurement of the natC( <italic>n,p</italic>) and natC( <italic>n,d</italic>) reactions from n_TOF at CERN

Motivated by recent extensions of the Gogny force standard expression <cross-ref refid='br0010' id='crf0220'>[1]</cross-ref>, we present here a new Hartree-Fock-Bogoliubov nuclear mass model based on an effective interaction including three ranges in the central term, employing a fitting procedure that includes a self-consistent account of quadrupole correlation energies within the 5-dimensional collective Hamiltonian approach. The newly adjusted parameterization, namely D3G3M, is the first of the Gogny type allowing to obtain all together a root mean square deviation as low as 870 keV over the 2457 nuclear masses accessible in the 2020 atomic mass evaluation, a stiff equation of state in neutron matter compatible with observed evidence for <math altimg='si1.svg'><mi>M</mi><mo linebreak='goodbreak' linebreakstyle='after'>&gt;</mo><mn>2</mn><msub><mrow><mi>M</mi></mrow><mrow><mo>&#8857;</mo></mrow></msub></math> heavy pulsars, and a correct neutron to proton effective masses hierarchy in asymmetric nuclear matter, making D3G3M both suited for nuclear structure calculations and astrophysical applications.

L. Batail

S. Goriely

S. Péru

S. Hilaire

D. Davesne

A. Pastore

A three-ranged Gogny-HFB nuclear mass model suited for astrophysical applications