Classical and Quantum Gravity最新文献

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

κ-general-relativity I: a non-commutative GR theory with the κ-Minkowski spacetime as its flat limit 广义相对论I：以广义-闵可夫斯基时空为平面极限的非交换广义相对论

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-10 DOI: 10.1088/1361-6382/adffdf

Daniel Rozental and Ofek Birnholtz

引用次数: 0

Associativity is enough: an all-orders 2d chiral algebra for 4d form factors 结合性是足够的：四维形状因子的全阶二维手性代数

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-10 DOI: 10.1088/1361-6382/ae0089

Víctor E Fernández and Natalie M Paquette

{"title":"Associativity is enough: an all-orders 2d chiral algebra for 4d form factors","authors":"Víctor E Fernández and Natalie M Paquette","doi":"10.1088/1361-6382/ae0089","DOIUrl":"https://doi.org/10.1088/1361-6382/ae0089","url":null,"abstract":"There is a special set of massless four-dimensional gauge theories which admit local and gauge-anomaly-free uplifts to twistor space; we call such theories twistorial. In twistorial theories, generalized towers of soft modes (including states of both helicities) form a 2d chiral algebra even at the quantum level. The 2d OPE limit of this chiral algebra coincides with the holomorphic collinear limit in 4d. This is true, in particular, for self-dual Yang–Mills theory coupled to special choices of matter, the latter being required to make the theory twistorial. Costello and the second author recently proposed that form factors of such twistorial 4d theories could be computed as 2d chiral algebra correlators. In turn, there exist form factors of self-dual theories, with insertions of appropriate local operators, that compute a subclass of observables in full (i.e. non-self-dual) QCD, coupled to appropriate matter. For example, the n-point two-loop all-plus QCD amplitude has recently been computed using the 1-loop chiral algebra OPEs determined thus far, but higher orders of the quantum-deformed chiral algebra must be determined to continue the ‘chiral algebra bootstrap’ program for higher-loop-level form factors of these twistorial theories. In this paper, using only elementary constraints from symmetries and associativity, we obtain closed-form expressions for the extended chiral algebra to arbitrary loop-order. This can be viewed as providing an all-loop result for a subset of collinear splitting functions in non-supersymmetric, massless QCD coupled to special choices of matter.","PeriodicalId":10282,"journal":{"name":"Classical and Quantum Gravity","volume":"130 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145032168","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

Periodic equatorial orbits in a black bounce scenario 黑色弹跳情景下的周期性赤道轨道

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-10 DOI: 10.1088/1361-6382/adffde

Anderson Bragado and Gonzalo J Olmo

引用次数: 0

Reconstructing source motion from gravitational wave strain 从引力波应变重建震源运动

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-10 DOI: 10.1088/1361-6382/adff33

Joe Bayley, Chris Messenger and Graham Woan

引用次数: 0

AthenaK simulations of the binary black hole merger GW150914 双黑洞合并GW150914的AthenaK模拟

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-10 DOI: 10.1088/1361-6382/adfffa

David Radice, Rossella Gamba, Hengrui Zhu and Alireza Rashti

引用次数: 0

Self-force and the Schwarzschild star 自作用力和史瓦西星

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-08 DOI: 10.1088/1361-6382/adfe4f

Abhinove N Seenivasan and Sam R Dolan

引用次数: 0

Testing compact, fused silica resonator based inertial sensors in a gravitational wave detector prototype facility 在引力波探测器原型设施中测试基于熔融硅谐振器的紧凑惯性传感器

IF 3.5 3区物理与天体物理

Classical and Quantum Gravity Pub Date : 2025-09-08 DOI: 10.1088/1361-6382/adff34

J J Carter, P Birckigt, J Lehmann, A Basalaev, S L Kranzhoff, S Al-Kershi, M Carlassara, G Chiarini, F Khan, G Leibeling, H Lück, C Rothhardt, S Risse, P Sarkar, S Takano, J von Wrangel, D S Wu and S M Koehlenbeck

{"title":"Testing compact, fused silica resonator based inertial sensors in a gravitational wave detector prototype facility","authors":"J J Carter, P Birckigt, J Lehmann, A Basalaev, S L Kranzhoff, S Al-Kershi, M Carlassara, G Chiarini, F Khan, G Leibeling, H Lück, C Rothhardt, S Risse, P Sarkar, S Takano, J von Wrangel, D S Wu and S M Koehlenbeck","doi":"10.1088/1361-6382/adff34","DOIUrl":"https://doi.org/10.1088/1361-6382/adff34","url":null,"abstract":"Future gravitational wave observatories require significant advances in all aspects of their seismic isolation; inertial sensors being a pressing example. Inertial sensors using gram-scale high mechanical Q factor (Q) glass resonators combined with compact interferometric readout are promising alternatives to kilogram-scale conventional inertial sensors. We have produced fused silica resonators suitable for low frequency inertial sensing and demonstrated that Qs of over 150 000 are possible. One resonator we produced was combined with a homodyne quadrature interferometer (HoQI) to read out the test mass displacement to form an inertial sensor. This is the first time a HoQI was used with a high Q resonator. The resulting sensor was tested against other commercial, kilogram scale inertial sensors at the AEI 10 m Prototype facility. Despite the dynamic range challenges induced by the test mass motion, we can match the excellent noise floors HoQIs have achieved so far with slow-moving or stationary test masses, showing HoQIs as an excellent candidate for the readout of such sensors. We evaluate the setup as an inertial sensor, showing the best performance demonstrated by any gram-scale sensor to date, with comparable sensitivity to the significantly bulkier sensors used in gravitational wave detectors today. These sensors’ compact size, self-calibration, and vacuum compatibility make them ideal candidates for the inertial sensing requirements in future gravitational wave detectors.","PeriodicalId":10282,"journal":{"name":"Classical and Quantum Gravity","volume":"14 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145017633","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