Classical and Quantum Gravity最新文献_第4页

A neural network for estimating compact binary coalescence parameters of gravitational-wave events in real time 一种实时估计引力波事件紧二进制合并参数的神经网络

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-17 DOI: 10.1088/1361-6382/ae0388

Sushant Sharma Chaudhary, Gianmarco Puleo and Marco Cavaglià

引用次数: 0

Noncommutative p-wave holographic superconductors 非对易p波全息超导体

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-16 DOI: 10.1088/1361-6382/ae02d9

Souvik Paul and Sunandan Gangopadhyay

引用次数: 0

Linearized gravity in the Starobinsky model: perturbative deviations from general relativity 斯塔宾斯基模型中的线性化重力：广义相对论的微扰偏差

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-16 DOI: 10.1088/1361-6382/ae02da

Roger Anderson Hurtado

{"title":"Linearized gravity in the Starobinsky model: perturbative deviations from general relativity","authors":"Roger Anderson Hurtado","doi":"10.1088/1361-6382/ae02da","DOIUrl":"https://doi.org/10.1088/1361-6382/ae02da","url":null,"abstract":"In this work, we linearize the field equations of f(R) gravity using the Starobinsky model, , and examine the modifications to general relativity (GR). We derive an equation for the trace, T, of the energy-momentum tensor, which we then decompose using an auxiliary field. This field satisfies the wave equation with T as its source, while simultaneously acting as an effective source for the classical deviation, , governed by the Klein–Gordon (KG) equation. The fields were expressed in terms of Green’s functions, whose symmetry properties facilitated the solution of the trace equation. Then was determined in terms of a modified or effective matter–energy distribution. From this, the effective energy density was obtained as the usual energy density T00, plus a perturbative correction proportional to m−2, involving the Laplacian of the integral of T, weighted by the retarded propagator of the KG equation. As an illustrative example, we numerically computed the perturbative term in a binary star system, evaluating it as a function of m and spatial position near the stars. In all cases, the results illustrate how the gravitational influence of the stars diminishes with distance, and how the perturbation decreases as m increases, consistently recovering the relativistic limit. Finally we computed the quadrupole components I11, I22, and I33 for m = 1 in the modified gravity model. The results show the same sinusoidal-squared structure as in GR, with I11 and I22 having equal but larger amplitudes, and I33 being negligible. We also numerically demonstrated that increasing m reduces the support of the Bessel-type function J1 modulated by a Heaviside factor, which governs the propagation close to the light cone, a physically expected effect. These results highlight the role of modified gravity corrections in the vicinity of compact objects.","PeriodicalId":10282,"journal":{"name":"Classical and Quantum Gravity","volume":"36 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145072472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

引用次数: 0

Exact analytic solutions in 2 + 1 ... 精确解析解在2 + 1…

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-15 DOI: 10.1088/1361-6382/ae0236

Jorge Bellorín, Claudio Bórquez and Byron Droguett

引用次数: 0

Research on collision simulation and control strategies for test mass release under electrostatic control 静电控制下试验质量释放的碰撞仿真与控制策略研究

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-15 DOI: 10.1088/1361-6382/ae0234

Diwen Shi(Daven Shi), Ji Wang, Chao Xue, Hengxu Yang, Jie Chang, Bingwei Cai, Yiyan Xu, Wei Wang, Shengping Huang and Jinxiu Zhang

{"title":"Research on collision simulation and control strategies for test mass release under electrostatic control","authors":"Diwen Shi(Daven Shi), Ji Wang, Chao Xue, Hengxu Yang, Jie Chang, Bingwei Cai, Yiyan Xu, Wei Wang, Shengping Huang and Jinxiu Zhang","doi":"10.1088/1361-6382/ae0234","DOIUrl":"https://doi.org/10.1088/1361-6382/ae0234","url":null,"abstract":"Space inertial sensors are crucial for space-based gravitational wave detection, requiring precise injection of test masses (TMs) into geodesic trajectories. However, conventional electrostatic suspension methods face challenges in capturing TMs with momentum exceeding . This study proposes a novel approach to mitigate TM release momentum by leveraging controlled collisions between the locking and release mechanism and the TM. A multi-body collision dynamics model, developed in MATLAB/Simulink, simulates the in-orbit injection process under space conditions, integrating low-speed collision contact detection and electrostatic interactions. The improved injection scheme employs momentum attenuation through plunger-TM collisions and utilizes electrostatic forces for orientation control, effectively expanding the allowable momentum range during release. Simulation results demonstrate that the strategy reduces TM momentum to capturable levels of 5 µm s−1 linear velocity and 150 µrad s−1 angular velocity within 300 s, even under non-ideal initial conditions. The collision-based method enhances injection reliability by addressing adhesion risks and momentum uncertainties, offering a robust solution for future gravitational wave detection missions.","PeriodicalId":10282,"journal":{"name":"Classical and Quantum Gravity","volume":"16 2 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145068100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

引用次数: 0

Constraining dirty black holes and pseudo-complex general relativity with the gravitational waves transient catalog 3.0 约束脏黑洞和伪复广义相对论与引力波瞬态表3.0

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-14 DOI: 10.1088/1361-6382/ae008a

Yehu I Maimon, Alex B Nielsen and Ofek Birnholtz

引用次数: 0

Can Transformers help us perform parameter estimation of overlapping signals in gravitational wave detectors? 变形金刚能否帮助我们对引力波探测器中的重叠信号进行参数估计？

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-14 DOI: 10.1088/1361-6382/adfd33

Lucia Papalini, Federico De Santi, Massimiliano Razzano, Ik Siong Heng and Elena Cuoco

{"title":"Can Transformers help us perform parameter estimation of overlapping signals in gravitational wave detectors?","authors":"Lucia Papalini, Federico De Santi, Massimiliano Razzano, Ik Siong Heng and Elena Cuoco","doi":"10.1088/1361-6382/adfd33","DOIUrl":"https://doi.org/10.1088/1361-6382/adfd33","url":null,"abstract":"Overlapping signals represent one of the major data analysis challenges in next-generation gravitational wave detectors. We leverage Transformers and Normalizing Flows, state-of-the-art machine learning algorithms, to address the parameter estimation of overlapping binary black hole mergers in the Einstein telescope (ET). Our proposed model combines a Transformer-based ‘Knowledge Extractor Neural Network’ (KENN) with a Normalizing Flow (HYPERION) to perform rapid and unbiased inference over multiple overlapping black hole binary events. The choice of architecture leverages the strength of Transformers in capturing complex and long-range temporal structures in the strain time series data, while Normalizing Flows provide a powerful framework to sample posterior distributions. We demonstrate the effectiveness and robustness of our model over simulated gravitational wave signals, showing that it maintains the same level of accuracy regardless of the correlation level in the data. Moreover our model provides estimates of chirp mass and coalescence times within –20% from the true simulated value. The results obtained are promising and show how this approach might represent a first step toward a deep-learning based inference pipeline for ET and other future gravitational wave detectors.","PeriodicalId":10282,"journal":{"name":"Classical and Quantum Gravity","volume":"20 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145059438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

引用次数: 0

Characteristics of tilt-to-length coupling coefficients for different time-delay interferometry combinations for LISA LISA不同延时干涉组合的倾斜-长度耦合系数特性

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-11 DOI: 10.1088/1361-6382/ae008b

Hao-Kang Chen, Pan-Pan Wang and Cheng-Gang Shao

{"title":"Characteristics of tilt-to-length coupling coefficients for different time-delay interferometry combinations for LISA","authors":"Hao-Kang Chen, Pan-Pan Wang and Cheng-Gang Shao","doi":"10.1088/1361-6382/ae008b","DOIUrl":"https://doi.org/10.1088/1361-6382/ae008b","url":null,"abstract":"Tilt-to-length (TTL) noise is one of the dominant noise sources in space-based gravitational wave (GW) detection. Methods such as the least squares estimator and the instrumental variables estimator can be employed to subtract TTL noise. A prerequisite for practical subtraction is the accurate estimation of the TTL coupling coefficients, whose characteristics depend on the performance of the specific time-delay interferometry (TDI) combinations. For instance, the Michelson-type TDI combinations allow the precise estimation of twelve TTL coefficients, while the Monitor-type and Relay-type combinations enable the estimation of sixteen TTL coefficients. This study systematically investigates the TTL coupling characteristics across forty-five geometric TDI combinations. We establish an exhaustive classification framework identifying each combination’s estimable TTL coefficient forms. Our findings reveal that among the combinations studied, only the Michelson-type combinations and present two TTL coefficients that are indistinguishable from one another. In contrast, we demonstrate that fully symmetric Sagnac combinations facilitate the estimation of all twenty-four TTL coefficients. Moreover, simulation results indicate that applying the least squares method subtracts TTL noise effectively, meeting the requirements of space-based GW detection.","PeriodicalId":10282,"journal":{"name":"Classical and Quantum Gravity","volume":"35 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145035321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

引用次数: 0

Cosmology in loop quantum gravity: symmetry reduction preserving gauge degrees of freedom 环量子引力中的宇宙学：保持规范自由度的对称约简

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-11 DOI: 10.1088/1361-6382/ae0088

Matteo Bruno

引用次数: 0

Noncommutative effects in Bianchi I cosmology with reduced relativistic gas 约化相对论气体的Bianchi I宇宙学中的非交换效应

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-11 DOI: 10.1088/1361-6382/adfff9

T M Abreu, G Oliveira-Neto, A C R Mendes and S C Reis

{"title":"Noncommutative effects in Bianchi I cosmology with reduced relativistic gas","authors":"T M Abreu, G Oliveira-Neto, A C R Mendes and S C Reis","doi":"10.1088/1361-6382/adfff9","DOIUrl":"https://doi.org/10.1088/1361-6382/adfff9","url":null,"abstract":"In this work, we investigate the effects of phase space noncommutativity on the dynamics of a Bianchi I (BI) cosmological model coupled to a reduced relativistic gas (RRG). The BI model provides a homogeneous but anisotropic framework suitable for exploring the transition from an early anisotropic Universe to the current isotropic stage. The RRG fluid interpolates between radiation and matter regimes, enabling a consistent treatment of the transition from the radiation-dominated to the matter-dominated era. In order to incorporate noncommutativity into the classical equations of motion, we employ the generalized symplectic formalism developed by Faddeev–Jackiw and extended by Barcelos–Wotzasek, which allows the introduction of noncommutative (NC) parameters via deformations in the symplectic structure. Within this approach, we derive a modified Hamiltonian expressed in terms of commutative variables that incorporate all NC effects. We then solve the resulting equations numerically and analyze the behavior of the scale factor and the anisotropic functions under variations of the NC parameters, as well as other physical and initial parameters of the model. Our results show that negative values of the NC parameters increase the expansion rate and reduce the isotropization timescale, partially mimicking the effect of a positive cosmological constant. We also estimate values for the NC parameters by numerically solving the integral expression for the age of the Universe, requiring consistency with observational data from the Planck 2018 mission. These findings support the possibility that noncommutativity may provide a geometric mechanism capable of accounting for the late-time acceleration and isotropization of the Universe, without requiring additional exotic energy components.","PeriodicalId":10282,"journal":{"name":"Classical and Quantum Gravity","volume":"38 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145035319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

引用次数: 0