To understand the contributions of ancient civilizations to the evolution of knowledge in the fields of archaeoastronomy and/or science in general, through a cognitive perspective, we seek to identify conceptual elements that are consonant and converge with science. All of them come from a cognitive processes in which the subject and the object of knowledge collaborate in a progressive constitution, according to Genetic Epistemology. It is necessary to identify the presence of logic as a mental structure that allows the subject to be capable of supporting the scientific work. In this article, we analyze dates that come from the inca's concept of Ayni which permeates the activities La Mint'a and La Mink'a and demonstrates the presence of the same cognitive structure—the logical—required by scientific work.
{"title":"Archaeoastronomy and Cognition: La Mink'a and La Mit'a From the Logic of Relations's Perspective","authors":"Mônica Estrázulas","doi":"10.1002/asna.70001","DOIUrl":"https://doi.org/10.1002/asna.70001","url":null,"abstract":"<div>\u0000 \u0000 <p>To understand the contributions of ancient civilizations to the evolution of knowledge in the fields of archaeoastronomy and/or science in general, through a cognitive perspective, we seek to identify conceptual elements that are consonant and converge with science. All of them come from a cognitive processes in which the subject and the object of knowledge collaborate in a progressive constitution, according to Genetic Epistemology. It is necessary to identify the presence of logic as a mental structure that allows the subject to be capable of supporting the scientific work. In this article, we analyze dates that come from the inca's concept of Ayni which permeates the activities La Mint'a and La Mink'a and demonstrates the presence of the same cognitive structure—the logical—required by scientific work.</p>\u0000 </div>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 3-4","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144206826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Markus Mugrauer, Ann-Kathrin Kollak, Lara Pietsch, Kai-Uwe Michel
In this paper, we present the latest results of our ongoing multiplicity survey of (Community) TESS Objects of Interest, using astrometry and photometry from the latest data release of the ESA Gaia mission to detect stellar companions of these stars and to characterize their properties. A total of 92 binary and two hierarchical triple star systems are identified among the 745 target stars whose multiplicity is explored in this study, all at distances of less than 500 pc around the Sun. As expected for components of gravitationally bound star systems, the targets and the detected companions are at the same distance and share a common proper motion, as shown by their accurate Gaia astrometry. The companions have masses of about 0.12 to 1.6 and are most frequently found in the mass range up to 0.6 . The companions have projected separations from the targets between about 110 and 9600 au. Their frequency is highest and constant from about 300 to 800 au, decreasing at larger projected separations. In addition to main sequence stars, five white dwarf companions are detected in this study, whose true nature is unveiled by their photometric properties.
{"title":"Gaia Search for Stellar Companions of TESS Objects of Interest V","authors":"Markus Mugrauer, Ann-Kathrin Kollak, Lara Pietsch, Kai-Uwe Michel","doi":"10.1002/asna.70005","DOIUrl":"https://doi.org/10.1002/asna.70005","url":null,"abstract":"<p>In this paper, we present the latest results of our ongoing multiplicity survey of (Community) TESS Objects of Interest, using astrometry and photometry from the latest data release of the ESA Gaia mission to detect stellar companions of these stars and to characterize their properties. A total of 92 binary and two hierarchical triple star systems are identified among the 745 target stars whose multiplicity is explored in this study, all at distances of less than 500 pc around the Sun. As expected for components of gravitationally bound star systems, the targets and the detected companions are at the same distance and share a common proper motion, as shown by their accurate Gaia astrometry. The companions have masses of about 0.12 to 1.6 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>M</mi>\u0000 <mo>⊙</mo>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {M}_{odot } $$</annotation>\u0000 </semantics></math> and are most frequently found in the mass range up to 0.6 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>M</mi>\u0000 <mo>⊙</mo>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {M}_{odot } $$</annotation>\u0000 </semantics></math>. The companions have projected separations from the targets between about 110 and 9600 au. Their frequency is highest and constant from about 300 to 800 au, decreasing at larger projected separations. In addition to main sequence stars, five white dwarf companions are detected in this study, whose true nature is unveiled by their photometric properties.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 5","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.70005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144482090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
João Gabriel Galli Gimenez, Dimiter Hadjimichef, César A. Zen Vasconcellos
We investigate the effects of a minimal measurable length on neutron stars, within the quantum hadrodynamics (QHD-I) model modified by the Generalized Uncertainty Principle (GUP). Working in a deformed Poisson algebra framework, we incorporate GUP effects via a time-invariant transformation of the phase space volume, effectively reducing the number of accessible quantum states at high momentum. We focus specifically on two observables critical to this star physics, the compressibility, which encapsulates how stiff EOS become, and the speed of sound, which imposes a causality constraint. Using this model as an exploratory study, due to its simplicity and structured description, we perform a preliminary analysis of GUP effects with a minimum spacetime length on these compact objects. This deformation increases the speed of sound while decreasing the compressibility, and we identify critical values of the Fermi momentum beyond which both quantities become nonphysical. These results underscore the potential role of a minimal length scale in shaping the bulk properties and possible phase structures of dense matter in neutron stars.
{"title":"Compressibility Function and Speed of Sound in the Non-Commutative Quantum Hadrodynamics Type-I Model for Neutron Stars","authors":"João Gabriel Galli Gimenez, Dimiter Hadjimichef, César A. Zen Vasconcellos","doi":"10.1002/asna.70008","DOIUrl":"https://doi.org/10.1002/asna.70008","url":null,"abstract":"<p>We investigate the effects of a minimal measurable length on neutron stars, within the quantum hadrodynamics (QHD-I) model modified by the Generalized Uncertainty Principle (GUP). Working in a deformed Poisson algebra framework, we incorporate GUP effects via a time-invariant transformation of the phase space volume, effectively reducing the number of accessible quantum states at high momentum. We focus specifically on two observables critical to this star physics, the compressibility, which encapsulates how stiff EOS become, and the speed of sound, which imposes a causality constraint. Using this model as an exploratory study, due to its simplicity and structured description, we perform a preliminary analysis of GUP effects with a minimum spacetime length on these compact objects. This deformation increases the speed of sound while decreasing the compressibility, and we identify critical values of the Fermi momentum beyond which both quantities become nonphysical. These results underscore the potential role of a minimal length scale in shaping the bulk properties and possible phase structures of dense matter in neutron stars.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 7-8","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.70008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145135193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recent observational results, such as those from pulsar timing arrays (PTA), suggest a low-frequency Gravitational Wave Background (GWB) permeates our universe. This opens the possibility that gravitational waves could span a broader spectrum, potentially impacting cosmological scales. Among novel Dark Energy (DE) models that explain DE as a very low-frequency GWB, the Compton Mass Dark Energy model (CMaDE) has shown promising theoretical alignment with cosmic acceleration. In this study, we explore the cosmological implications of the CMaDE model when coupled with Scalar Field Dark Matter (SFDM) as the dark matter candidate. We numerically solve the cosmological evolution equations for this combined CMaDE+SFDM framework, examining its impact on key observables and comparing results to the standard model. Our findings demonstrate that the CMaDE+SFDM model is broadly consistent with , showing similar evolution in observables such as the cosmic microwave background and the background energy densities, with some deviations that merit further investigation.
{"title":"Dark Energy From the Gravitational Wave Background With Scalar Field Dark Matter","authors":"Edwin L. Pérez-Ochoa, Tonatiuh Matos","doi":"10.1002/asna.70004","DOIUrl":"https://doi.org/10.1002/asna.70004","url":null,"abstract":"<p>Recent observational results, such as those from pulsar timing arrays (PTA), suggest a low-frequency Gravitational Wave Background (GWB) permeates our universe. This opens the possibility that gravitational waves could span a broader spectrum, potentially impacting cosmological scales. Among novel Dark Energy (DE) models that explain DE as a very low-frequency GWB, the Compton Mass Dark Energy model (CMaDE) has shown promising theoretical alignment with cosmic acceleration. In this study, we explore the cosmological implications of the CMaDE model when coupled with Scalar Field Dark Matter (SFDM) as the dark matter candidate. We numerically solve the cosmological evolution equations for this combined CMaDE+SFDM framework, examining its impact on key observables and comparing results to the standard <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>ΛCDM</mi>\u0000 </mrow>\u0000 <annotation>$$ Lambda mathrm{CDM} $$</annotation>\u0000 </semantics></math> model. Our findings demonstrate that the CMaDE+SFDM model is broadly consistent with <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>ΛCDM</mi>\u0000 </mrow>\u0000 <annotation>$$ Lambda mathrm{CDM} $$</annotation>\u0000 </semantics></math>, showing similar evolution in observables such as the cosmic microwave background and the background energy densities, with some deviations that merit further investigation.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 3-4","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.70004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144207028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The physics of heavy-ion collisions is one of the most exciting and challenging directions of science for the last four decades. On the theoretical side one deals with a non-abelian field theory, while on the experimental side today's largest accelerators are needed to enable these studies. The discovery of a new stage of matter—called the quark-gluon plasma (QGP) - and the study of its properties is one of the major achievements of modern physics. In this contribution we briefly review the history of theoretical descriptions of heavy-ion collisions based on dynamical models, focusing on the personal experiences in this inspiring field.
{"title":"The Quest for the Quark-Gluon Plasma From the Perspective of Dynamical Models of Relativistic Heavy-Ion Collisions","authors":"Marcus Bleicher, Elena Bratkovskaya","doi":"10.1002/asna.70006","DOIUrl":"https://doi.org/10.1002/asna.70006","url":null,"abstract":"<p>The physics of heavy-ion collisions is one of the most exciting and challenging directions of science for the last four decades. On the theoretical side one deals with a non-abelian field theory, while on the experimental side today's largest accelerators are needed to enable these studies. The discovery of a new stage of matter—called the quark-gluon plasma (QGP) - and the study of its properties is one of the major achievements of modern physics. In this contribution we briefly review the history of theoretical descriptions of heavy-ion collisions based on dynamical models, focusing on the personal experiences in this inspiring field.</p>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 7-8","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.70006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145135381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
<div> <p>The search for new states of matter has been the subject of study and research, as well as their identification in colliders, with exotic states being identified in experiments around the world in recent years. Among the possible exotic states provided in QCD we have the glueball, a bound state between gluons. Using a non-relativistic gluon bound state model, we calculate <span></span><math> <semantics> <mrow> <mi>Γ</mi> <mrow> <mo>(</mo> <mrow> <mi>G</mi> <mo>→</mo> <mrow> <mi>γ</mi> <mi>γ</mi> </mrow> </mrow> <mo>)</mo> </mrow> </mrow> <annotation>$$ Gamma left(Gto gamma gamma right) $$</annotation> </semantics></math>, where <span></span><math> <semantics> <mrow> <mi>G</mi> </mrow> <annotation>$$ G $$</annotation> </semantics></math> is a pseudoscalar digluon (<span></span><math> <semantics> <mrow> <msup> <mn>0</mn> <mrow> <mo>−</mo> <mo>+</mo> </mrow> </msup> </mrow> <annotation>$$ {0}^{-+} $$</annotation> </semantics></math>), which is applied to a possible exotic state, the meson <span></span><math> <semantics> <mrow> <mi>X</mi> <mrow> <mo>(</mo> <mn>1835</mn> <mo>)</mo> </mrow> </mrow> <annotation>$$ X(1835) $$</annotation> </semantics></math>. We start from the amplitudes, where we consider the process <span></span><math> <semantics> <mrow> <mrow> <mi>γ</mi> <mi>γ</mi> </mrow> <mo>→</mo> <msup> <mi>g</mi> <mo>*</mo> </msup> <msup> <mi>g</mi> <mo>*</mo> </msup> </mrow> <annotation>$$ gamma gamma to {g}^{ast }{g}^{ast } $$</annotation> </semantics></math>, with the <i>g</i>*s being the massive constituent gluons and the amplitudes obtained in the lowest-order perturbative QCD deriving them from the QED calculation. The unknown parameters of the model such as the digluon wavefunction are obtained using experimentally measured values of the decay of <span></span><math>
{"title":"Glueball-Like Decay of X(1835) Into Two Photons","authors":"D. T. Da Silva, M. L. L. Da Silva","doi":"10.1002/asna.20250030","DOIUrl":"https://doi.org/10.1002/asna.20250030","url":null,"abstract":"<div>\u0000 \u0000 <p>The search for new states of matter has been the subject of study and research, as well as their identification in colliders, with exotic states being identified in experiments around the world in recent years. Among the possible exotic states provided in QCD we have the glueball, a bound state between gluons. Using a non-relativistic gluon bound state model, we calculate <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>Γ</mi>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mrow>\u0000 <mi>G</mi>\u0000 <mo>→</mo>\u0000 <mrow>\u0000 <mi>γ</mi>\u0000 <mi>γ</mi>\u0000 </mrow>\u0000 </mrow>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation>$$ Gamma left(Gto gamma gamma right) $$</annotation>\u0000 </semantics></math>, where <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>G</mi>\u0000 </mrow>\u0000 <annotation>$$ G $$</annotation>\u0000 </semantics></math> is a pseudoscalar digluon (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mn>0</mn>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mo>+</mo>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation>$$ {0}^{-+} $$</annotation>\u0000 </semantics></math>), which is applied to a possible exotic state, the meson <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>X</mi>\u0000 <mrow>\u0000 <mo>(</mo>\u0000 <mn>1835</mn>\u0000 <mo>)</mo>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation>$$ X(1835) $$</annotation>\u0000 </semantics></math>. We start from the amplitudes, where we consider the process <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mrow>\u0000 <mi>γ</mi>\u0000 <mi>γ</mi>\u0000 </mrow>\u0000 <mo>→</mo>\u0000 <msup>\u0000 <mi>g</mi>\u0000 <mo>*</mo>\u0000 </msup>\u0000 <msup>\u0000 <mi>g</mi>\u0000 <mo>*</mo>\u0000 </msup>\u0000 </mrow>\u0000 <annotation>$$ gamma gamma to {g}^{ast }{g}^{ast } $$</annotation>\u0000 </semantics></math>, with the <i>g</i>*s being the massive constituent gluons and the amplitudes obtained in the lowest-order perturbative QCD deriving them from the QED calculation. The unknown parameters of the model such as the digluon wavefunction are obtained using experimentally measured values of the decay of <span></span><math>\u0000 ","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 3-4","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144206442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ulrich Heber, Maximilian Halenke, Aakash Bhat, Veronika Schaffenroth
We report the discovery of the young B6 V run-away star LAMOST J083323.18 + 430825.4, 2.5 kpc above the Galactic plane. Its atmospheric parameters and chemical composition are determined from LAMOST spectra, indicating normal composition. Effective temperature ( = K) and gravity ( = ) suggest that the star is close to terminating hydrogen burning. An analysis of the spectral energy distribution allowed us to determine the angular diameter as well as the interstellar reddening. Using evolutionary models from the MIST database we derived the stellar mass () and age ( Myr). The spectroscopic distance (4.17 kpc), the radius (), and the luminosity (<
{"title":"A Slowly Pulsating Run-Away B Star at High Galactic Latitude Ejected From a Spiral Arm","authors":"Ulrich Heber, Maximilian Halenke, Aakash Bhat, Veronika Schaffenroth","doi":"10.1002/asna.70003","DOIUrl":"https://doi.org/10.1002/asna.70003","url":null,"abstract":"<p>We report the discovery of the young B6 V run-away star LAMOST J083323.18 + 430825.4, 2.5 kpc above the Galactic plane. Its atmospheric parameters and chemical composition are determined from LAMOST spectra, indicating normal composition. Effective temperature (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>T</mi>\u0000 <mi>eff</mi>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {T}_{mathrm{eff}} $$</annotation>\u0000 </semantics></math> = <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>14,500</mn>\u0000 </mrow>\u0000 <annotation>$$ mathrm{14,500} $$</annotation>\u0000 </semantics></math> K) and gravity (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>log</mi>\u0000 <mi>g</mi>\u0000 </mrow>\u0000 <annotation>$$ log g $$</annotation>\u0000 </semantics></math> = <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>3.79</mn>\u0000 </mrow>\u0000 <annotation>$$ 3.79 $$</annotation>\u0000 </semantics></math>) suggest that the star is close to terminating hydrogen burning. An analysis of the spectral energy distribution allowed us to determine the angular diameter as well as the interstellar reddening. Using evolutionary models from the MIST database we derived the stellar mass (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>4.75</mn>\u0000 <msub>\u0000 <mi>M</mi>\u0000 <mo>⊙</mo>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ 4.75{M}_{odot } $$</annotation>\u0000 </semantics></math>) and age (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msubsup>\u0000 <mn>104</mn>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>13</mn>\u0000 </mrow>\u0000 <mrow>\u0000 <mo>+</mo>\u0000 <mn>11</mn>\u0000 </mrow>\u0000 </msubsup>\u0000 </mrow>\u0000 <annotation>$$ {104}_{-13}^{+11} $$</annotation>\u0000 </semantics></math> Myr). The spectroscopic distance (4.17 kpc), the radius (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>4.5</mn>\u0000 <msub>\u0000 <mi>R</mi>\u0000 <mo>⊙</mo>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ 4.5{R}_{odot } $$</annotation>\u0000 </semantics></math>), and the luminosity (<span></span><","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 5","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/asna.70003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144482185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhi-Fu Gao, Xin-Jun Zhao, Xiao-Feng Yang, Wen-Qi Ma, Zi-Rui Hu
This work provides a comprehensive analysis of modifications to the Einstein–Hilbert action, with a particular focus on Gauss–Bonnet (GB) gravity, and addresses the theoretical challenges in unifying quantum gravity frameworks with the GB gravitational modifications. By developing a novel fourth-order tensor methodology to manage derivative couplings, we establish a stable framework that eliminates higher-order derivative instabilities while enabling modified gravitational phenomena. The model maintains consistency with low-energy string theory constraints and generates testable predictions for black hole thermodynamics and cosmic expansion dynamics. Our results reconcile discrepancies between modified gravity theories and quantum field theory requirements, providing new mathematical tools for analyzing high-energy gravitational interactions. This work bridges critical gaps between theoretical formulations and observational evidence in cosmology, offering a unified approach to modeling gravitational interactions across quantum and cosmological scales.
{"title":"Modified Field Equation With Gauss–Bonnet Gravity","authors":"Zhi-Fu Gao, Xin-Jun Zhao, Xiao-Feng Yang, Wen-Qi Ma, Zi-Rui Hu","doi":"10.1002/asna.20250027","DOIUrl":"https://doi.org/10.1002/asna.20250027","url":null,"abstract":"<div>\u0000 \u0000 <p>This work provides a comprehensive analysis of modifications to the Einstein–Hilbert action, with a particular focus on Gauss–Bonnet (GB) gravity, and addresses the theoretical challenges in unifying quantum gravity frameworks with the GB gravitational modifications. By developing a novel fourth-order tensor methodology to manage derivative couplings, we establish a stable framework that eliminates higher-order derivative instabilities while enabling modified gravitational phenomena. The model maintains consistency with low-energy string theory constraints and generates testable predictions for black hole thermodynamics and cosmic expansion dynamics. Our results reconcile discrepancies between modified gravity theories and quantum field theory requirements, providing new mathematical tools for analyzing high-energy gravitational interactions. This work bridges critical gaps between theoretical formulations and observational evidence in cosmology, offering a unified approach to modeling gravitational interactions across quantum and cosmological scales.</p>\u0000 </div>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 7-8","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145135764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
César Augusto Zen Vasconcellos, Peter Hess, Fridolin Weber, Remo Ruffini, Jorge Horvath, Zhifu Gao, Dimiter Hadjimichef, Benno Bodmann
This Conference Proceedings volume contains the written versions of most of the contributions presented during the 11th International Workshop on Astronomy and Relativistic Astrophysics (IWARA 2024). The Workshop took place in Machupicchu Pueblo (Aguas Calientes), Peru, from September 2–6, 2024. The Workshop provided a setting for discussing recent developments in a wide variety of topics, including Archaeoastronomy and Cognition, the Kerr metric and the Hawking temperature, Damour-Solodukhin-type Wormholes, Stellar Physics and General Relativity, Stochastic Quantum Mechanics in Curved Spaces, Gauss-Bonnet Theory, Quantum Gravity, Black Holes, Fast Radio Bursts, Neutron Stars, Strange Stars, X-ray Binaries, Pulsars, Gravitational Waves, and Dark Matter, among others. Most of these contributions are included in this volume.
{"title":"Preface to the 11th International Workshop on Astronomy and Relativistic Astrophysics (IWARA 2024)","authors":"César Augusto Zen Vasconcellos, Peter Hess, Fridolin Weber, Remo Ruffini, Jorge Horvath, Zhifu Gao, Dimiter Hadjimichef, Benno Bodmann","doi":"10.1002/asna.20250042","DOIUrl":"https://doi.org/10.1002/asna.20250042","url":null,"abstract":"<div>\u0000 \u0000 <p>This Conference Proceedings volume contains the written versions of most of the contributions presented during the 11th International Workshop on Astronomy and Relativistic Astrophysics (IWARA 2024). The Workshop took place in Machupicchu Pueblo (Aguas Calientes), Peru, from September 2–6, 2024. The Workshop provided a setting for discussing recent developments in a wide variety of topics, including Archaeoastronomy and Cognition, the Kerr metric and the Hawking temperature, Damour-Solodukhin-type Wormholes, Stellar Physics and General Relativity, Stochastic Quantum Mechanics in Curved Spaces, Gauss-Bonnet Theory, Quantum Gravity, Black Holes, Fast Radio Bursts, Neutron Stars, Strange Stars, X-ray Binaries, Pulsars, Gravitational Waves, and Dark Matter, among others. Most of these contributions are included in this volume.</p>\u0000 </div>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 3-4","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144206980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
MAXI J1820+070, discovered by the Monitor of All-sky X-ray Image (MAXI) in 2018, is a well-known black hole X-ray binary. This study presents a detailed spectral analysis using 2018 observations from the Insight Hard X-ray Modulation Telescope (HXMT). We explored the evolution of the Fe line shape and found it stable at 6.4 keV in the high/soft state, indicating the inner radius of the accretion disk remains at the Innermost Stable Circular Orbit. Additionally, we estimated the black hole spin () using the continuum fitting method, obtaining a spin of , consistent with previous results. Through these findings, this study has contributed to the spectral analysis and spin parameter estimation of black hole X-ray binary systems, offering valuable insights into black hole behavior and its role in cosmology.
{"title":"Estimating the Spin of MAXI J1820+070 From Soft State by Insight-HXMT","authors":"Chun-Xiang Liao, Chao Huang, Jian-Chao Feng, Ai-Jun Dong","doi":"10.1002/asna.20250021","DOIUrl":"https://doi.org/10.1002/asna.20250021","url":null,"abstract":"<div>\u0000 \u0000 <p>MAXI J1820+070, discovered by the Monitor of All-sky X-ray Image (MAXI) in 2018, is a well-known black hole X-ray binary. This study presents a detailed spectral analysis using 2018 observations from the Insight Hard X-ray Modulation Telescope (HXMT). We explored the evolution of the Fe line shape and found it stable at 6.4 keV in the high/soft state, indicating the inner radius of the accretion disk remains at the Innermost Stable Circular Orbit. Additionally, we estimated the black hole spin (<span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>a</mi>\u0000 <mo>*</mo>\u0000 </msub>\u0000 </mrow>\u0000 <annotation>$$ {a}_{ast } $$</annotation>\u0000 </semantics></math>) using the continuum fitting method, obtaining a spin of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>a</mi>\u0000 <mo>*</mo>\u0000 </msub>\u0000 <msubsup>\u0000 <mrow>\u0000 <mo>=</mo>\u0000 <mn>0.122</mn>\u0000 </mrow>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>0.016</mn>\u0000 </mrow>\u0000 <mrow>\u0000 <mo>+</mo>\u0000 <mn>0.013</mn>\u0000 </mrow>\u0000 </msubsup>\u0000 </mrow>\u0000 <annotation>$$ {a}_{ast }={0.122}_{-0.016}^{+0.013} $$</annotation>\u0000 </semantics></math>, consistent with previous results. Through these findings, this study has contributed to the spectral analysis and spin parameter estimation of black hole X-ray binary systems, offering valuable insights into black hole behavior and its role in cosmology.</p>\u0000 </div>","PeriodicalId":55442,"journal":{"name":"Astronomische Nachrichten","volume":"346 7-8","pages":""},"PeriodicalIF":1.0,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145135554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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