检索结果-内蒙古大学图书馆

Joint observations of late universe probes: cosmological parameter constraints from gravitational wave and Type Ia supernova data

学校读者我要写书评

暂无评论

arXiv 2024年

作者： Zheng, Jie Liu, Xiao-Hui Qi, Jing-Zhao Gravitational Wave Observatory Henan Academy of Sciences Zhengzhou450046 China National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China School of Astronomy and Space Science University of Chinese Academy of Sciences Beijing100049 China Department of Physics College of Sciences MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China

The growing tensions between the early Universe and the late Universe increasingly highlight the importance of developing precise probes for late cosmology. As significant late-Universe probes, Type Ia supernovae (SNe Ia) and gravitational waves (GWs) can provide measurements of relative and absolute distances, respectively. Their complementary nature is likely to break the degeneracies among cosmological parameters, thereby yielding more precise constraints. In this study, we use 43 gravitationalwave sources from the Third LIGO-Virgo-KAGRA Gravitational-Wave Transient Catalog (GWTC-3) and 1590 SNe Ia from Pantheon+ compilation to constrain the dark energy models, as an attempt to achieve precise late-Universe cosmological constraints. For the dark siren GW event, we estimate the corresponding redshift using the binary black hole redshift distribution model. The combination of GW and SNe Ia data could provide the precision on the Hubble constant H0 and the present matter density Ωm of approximately 20% and 8% for the ΛCDM model. If we consider the equation of state of dark energy w, the combination sample constrain the precision of w to approximately 30%. Although the combination of GW and SNe Ia observations effectively breaks degeneracies among various cosmological parameters, yielding more stringent constraints, the precision of these constraints still does not meet the stringent standards required by precision cosmology. However, it is reasonable to anticipate that, in the near future, the joint observations of GWs and SNe Ia will become a powerful tool, particularly in the late Universe, for the precise measurement of cosmological parameters. Copyright © 2024, The Authors. All rights reserved.

关键词： Gravity waves

A novel method of measuring cosmological distances using broad-line regions of quasars

学校读者我要写书评

暂无评论

arXiv 2020年

作者： Li, Hong Zhang, Xin Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing100049 China Department of Physics College of Sciences Northeastern University Shenyang110819 China Ministry of Education’s Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China Center for High Energy Physics Peking University Beijing100080 China Center for Gravitation and Cosmology Yangzhou University Yangzhou225009 China

Our ancestors, such as Cro-Magnon, always looked up at the stars and wished to understand the mysteries of the universe, but their view of the universe was probably quite simple: the stars are inlaid on the inner surface of the sky, and they are very small. However, now we know that stars and galaxies are actually extremely huge, and they look small because they are too far away from us. This indicates that the measurement of cosmological distance is always very important in the study of the universe. Due to the expansion of the cosmos, the stars we see are actually what they used to be. The wavelength of light emitted from a star becomes longer due to the expansion of the universe, which is called "redshift of light". The larger the redshift, the older is the star. If we can measure both the distances and redshifts of stars (luminous objects), we can then establish a relationship between distance and redshift, from which the information of cosmic expansion history can be obtained. Actually, the measurement of the expansion history of the universe can answer the fundamental questions about the cosmos, such as its age, geometry, composition, and so forth. Copyright © 2020, The Authors. All rights reserved.

关键词： Stars

Dark energy and matter interacting scenario to relieve H_(0) and S_(8) tensions

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第5期48卷 1-7页

作者：高立场薛社生张鑫 Key Laboratory of Cosmology and Astrophysics(Liaoning Province)&Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Kapteyn Astronomical Institute University of GroningenP.O.Box 8009700 AV Groningenthe Netherlands ICRANet Piazzale della Repubblica10-65122PescaraItaly ICTP-AP University of Chinese Academy of SciencesBeijing 100049China Physics Department Sapienza University of RomeP.le A.Moro 500185RomeItaly INFN Sezione di PerugiaVia A.PascoliI-06123PerugiaItaly Key Laboratory of Data Analytics and Optimization for Smart Industry(Ministry of Education) Northeastern UniversityShenyang 110819China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityShenyang 110819China

We consider a new cosmological model(calledΛCDM),in which the vacuum energy interacts with matter and radiation,and test this model using the current cosmological *** the CMB+BAO+SN(CBS)dataset to constrain the model,we find that H_(0) and S_(8) tensions are relieved to 2.87σand 2.77σ,***,in this case,theΛCDM model is not favored by the data,compared withΛ*** find that when the H_(0) and S_(8) data are added to the data combination,the situation is significantly *** the CBS+H_(0) case,the model relieves the H_(0) tension to 0.47σ,and the model is favored overΛ*** the CBS+H_(0)+S_(8) case,we obtain a synthetically best situation,in which the H_(0) and S_(8) tensions are relieved to 0.72σand 2.11σ,*** this case,the model is most favored by the ***,this cosmological model can greatly relieve the H_(0) tension and simultaneously effectively alleviate the S_(8) tension.

关键词： dark energy interacting dark energy model the Hubble constant Hubble tension cosmological constraint

Decomposition is All You Need: Single-Objective to Multi-Objective optimization Towards Responsible Artificial General Intelligence

学校读者我要写书评

暂无评论

SSRN

SSRN 2024年

作者： Wendi, Xu Yuemao, Zhao Ming, Zhang College of Energy and Mining Engineering Shandong University of Science and Technology Qingdao266590 China National Frontier Sciences Center for Industrial Intelligence and Systems Optimization Ministry of Education China College of Information Science and Engineering Northeastern University United States Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education China Xinjiang Astronomical Observatory Chinese Academy of Sciences China Key Laboratory for Radio Astronomy Chinese Academy of Sciences Nanjing China University of Chinese Academy of Sciences China Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Shenyang110819 China

Responsible artificial general intelligence (AGI) is deeply connected with both explainable artificial intelligence and interpretable artificial intelligence. In frontier science of evolutionary transfer optimization (ETO) towards responsible AGI, transfer core (TC) is both explainable and responsible for single-objective to multi-objective optimization (SMO) that can harness comprehensive intelligent models for complex task-solving. From both theoretical and practical sides, we get the work of "HMeets" (this paper) for SMO on TC in both production and logistic systems. In HMeets, TC is further confirmed its role or responsibility for selection pressure, which performs general-purpose problem-solving abilities. We tend to believe that TC or SMO maybe serves as a fundamental concept and common tool like what happens in ResNets, Transformers and WARSHIP (our visual AGI) for wildly applications beyond manufacturing here in the future. © 2024, The Authors. All rights reserved.

关键词： Multiobjective optimization

Understanding Co2 Adsorption in Layered Double Oxides Synthesized by Slag Through Kinetic and Modelling Techniques

学校读者我要写书评

暂无评论

SSRN

SSRN 2023年

作者： Duan, Wenjun Han, Jiachen Yang, Shuo Wang, Zhimei Yu, Qingbo Zhan, Yaquan School of Metallurgy Northeastern University No 11 Lane 3 Wenhua Road Heping District Liaoning Shenyang110819 China College of Energy and Environment Shenyang Aerospace University No. 37 Daoyi South Street Shenbei New District Liaoning Shenyang110136 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry [Northeastern University Ministry of Education China

A novel technology for high-value utilization of blast furnace slag, a main by-product in iron and steel industry, was proposed to address CO2 capture. Layered double hydroxides derived from blast furnace slag served as the raw material for producing efficient CO2 adsorbents, referred to as layered double oxides. Detailed investigations were conducted to compare the characteristics of the raw material and the resulting adsorbent. Significantly, the laminate structure of layered double hydroxides changed in microstructure, particle size distribution and functional groups. In thermal transformation, about 30% weight was lost, forming layered double oxides with CaO, Ca12Al14O32Cl2 and MgO phases. The transformation mechanism for preparing layered double oxides was elucidated. Additionally, the CO2 adsorption performance of layered double oxides was studied, and a suitable kinetic model was established. Under conditions of 15% CO2 concentration and 873 K temperature, the sample exhibited a CO2 capacity of approximately 147.49 mg‧g-1. The optimal kinetic mechanism model for CO2 adsorption was identified as PSO, with activation energy and pre-exponential factors of 56.88 kJ‧mol-1 and 12.26 min-1, respectively. This study successfully achieved dual goals: reducing CO2 emissions and maximizing the value of solid waste in iron and steel industry. © 2023, The Authors. All rights reserved.

关键词： Slags

Effects of Small-Scale Absorption Systems on Neutral Islands during the Late Epoch of Reionization

学校读者我要写书评

暂无评论

arXiv 2021年

作者： Wu, Peng-Ju Xu, Yidong Zhang, Xin Chen, Xuelei Department of Physics College of Sciences Northeastern University Shenyang110819 China National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Shenyang110819 China Center for High Energy Physics Peking University Beijing100871 China University of Chinese Academy of Sciences Beijing100049 China

The reionization process is expected to be prolonged by the small-scale absorbers (SSAs) of ionizing photons, which have been seen as Lyman-limit systems in quasar absorption line observations. We use a set of semi-numerical simulations to investigate the effects of absorption systems on the reionization process, especially their impacts on the neutral islands during the late Epoch of Reionization (EoR). Three models are studied, i.e. the extreme case of no-SSA model with a high level of ionizing background, the moderate-SSA model with a relatively high level of ionizing background, and the dense-SSA model with a low level of ionizing background. We find that while the characteristic scale of neutral regions decreases during the early and middle stages of reionization, it stays nearly unchanged at about 10 comoving Mpc during the late stage for the no-SSA and moderate-SSA models. However, in the case of weak ionizing background in the dense-SSA model, the characteristic island scale shows obvious evolution, as large islands break into many small ones that are slowly ionized. The evolutionary behavior of neutral islands during the late EoR thus provides a novel way to constrain the abundance of SSAs. We discuss the 21-cm observation with the upcoming Square Kilometre Array. The different models can be distinguished by either the 21-cm imaging or the 21-cm power spectrum measurements. Copyright © 2021, The Authors. All rights reserved.

关键词：

Cosmology with fast radio bursts in the era of SKA

学校读者我要写书评

暂无评论

arXiv 2023年

作者： Zhang, Ji-Guo Zhao, Ze-Wei Li, Yichao Zhang, Jing-Fei Li, Di Zhang, Xin Department of Physics College of Sciences Northeastern University Shenyang110819 China Northeastern University Shenyang110819 China National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China University of Chinese Academy of Sciences Beijing100049 China Research Center for Intelligent Computing Platforms Zhejiang Laboratory Hangzhou311100 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Shenyang110819 China

We present a forecast of the cosmological parameter estimation using fast radio bursts (FRBs) from the upcoming Square Kilometre Array (SKA), focusing on the issues of dark energy, the Hubble constant, and baryon density. We simulate 105 and 106 localized FRBs from a 10-year SKA observation, and find that: (i) using 106 FRB data alone can tightly constrain dark-energy equation of state parameters better than CMB+BAO+SNe, providing an independent cosmological probe to explore dark energy;(ii) combining the FRB data with gravitational-wave standard siren data from 10-year observation with the Einstein Telescope, the Hubble constant can be constrained to a sub-percent level, serving as a powerful low-redshift probe;(iii) using 106 FRB data can constrain the baryon density Ωbh to a precision of ∼ 0.1%. Our results indicate that SKA-era FRBs will provide precise cosmological measurements to shed light on both dark energy and the missing baryon problem, and help resolve the Hubble tension. Copyright © 2023, The Authors. All rights reserved.

关键词： Cosmology

Exploring neutrino mass and mass hierarchy in interacting dark energy models

学校读者我要写书评

暂无评论

arXiv 2019年

作者： Feng, Lu Li, Hai-Li Zhang, Jing-Fei Zhang, Xin College of Physical Science and Technology Shenyang Normal University Shenyang110034 China Department of Physics College of Sciences Northeastern University Shenyang110819 China Ministry of Education Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China Center for High Energy Physics Peking University Beijing100080 China Center for Gravitation and Cosmology Yangzhou University Yangzhou225009 China

We investigate how the dark energy properties impact the constraints on the total neutrino mass in interacting dark energy (IDE) models. In this study, we focus on two typical interacting dynamical dark energy models, i.e., the interacting w cold dark matter (IwCDM) model and the interacting holographic dark energy (IHDE) model. To avoid the large-scale instability problem in IDE models, we apply the parameterized post-Friedmann approach to calculate the perturbation of dark energy. We employ the Planck 2015 cosmic microwave background temperature and polarization data, combined with low-redshift measurements on baryon acoustic oscillation distance scales, type Ia supernovae, and the Hubble constant, to constrain the cosmological parameters. We find that the dark energy properties could influence the constraint limits on the total neutrino mass. Once dynamical dark energy is considered in the IDE models, the upper bounds of P mν will be changed. By considering the values of χ2min, we find that in these IDE models the normal hierarchy case is slightly preferred over the inverted hierarchy case;for example, ∆χ2 = 2.720 is given in the IHDE+P mν model. In addition, we also find that in the IwCDM+P mν model β = 0 is consistent with current observational data inside the 1σ range, and in the IHDE+P mν model β > 0 is favored at more than 2σ level. Copyright © 2019, The Authors. All rights reserved.

关键词： Microwave oscillators

Texture and microstructure evolution of 321 austenitic stainless steel ultra-thin strip during asynchronous rolling

学校读者我要写书评

暂无评论

IOP Conference Series: Materials Science and Engineering 2020年第1期892卷

作者： Jingqi Chen Liuqing Yang Xianlei Hu Xianghua Liu State Key Laboratory of Rolling and Automation Northeastern University Shengyang 110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry (Northeastern University) Ministry of Education Shengyang 110819 China

This paper studied the evolution of texture and microstructure of 321 austenitic stainless steel ultra-thin strip during asynchronous rolling. Experimental results show that during the process of asynchronous rolling, the martensitic structure mainly forms such kinds of texture, as {111} <110> Z texture, {111} <112> Y texture, {001} <110> R-CubeND texture, {112} <110> Cu texture, and {110} <110> Goss texture. With the increase of deformation, the strengths of {111} <112> Y texture, {001} <110> R-CubeND texture, {112} <110> Cu texture, and {110} <110> Goss texture increase first and then decrease. In the early stage of rolling, dislocation slip is the main plastic deformation, followed by deformation twins in the high strain region, which prevents further dislocation slip. When the rolling pressure rate is greater than 50%, the deformation induces rapid growth in the content of the martensite, with the continued nucleation and growth of the deformation twins.

关键词：