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Probing a polymerized black hole with the frequency shifts of photons

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arXiv 2022年

作者： Fu, Qi-Ming Zhang, Xin College of Sciences Northeastern University Shenyang110819 China Institute of Physics Shaanxi University of Technology Hanzhong723000 China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Shenyang110819 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China

As is well-known, black hole plays an important role in probing the quantum effects of gravity in the strong-field regime. In this paper, we focus on a polymerized black hole and investigate the quantum effects on the redshift, blueshift and gravitational redshift of photons emitted by massive particles revolving around this black hole. With a general relativistic formalism, we obtain two elegant and concise expressions for the mass of the black hole and the quantum parameter in terms of few direct observables, and find that all the frequency shifts of photons decrease with the quantum parameter. By expanding the total frequency shift for large orbit of the emitter, low peculiar redshift, and small azimuthal angle, we find that the leading contributions to the frequency shift are originated from the kinematic shift and peculiar shift, and the quantum effects make a negligible contribution. In addition, we study the effects of the plasma on the redshift/blueshift for the first time, and conclude that the presence of plasma results in the decrease of the redshift/blueshift. Copyright © 2022, The Authors. All rights reserved.

关键词： Black holes

Prospects for measuring dark energy with 21 cm intensity mapping experiments

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arXiv 2021年

作者： Wu, Peng-Ju Zhang, Xin Department of Physics College of Sciences Northeastern University Shenyang110819 China MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China

Using the 21 cm intensity mapping (IM) technique can efficiently perform large-scale neutral hydrogen (H i) surveys, and this method has great potential for measuring dark-energy parameters. Some 21 cm IM experiments aiming at measuring dark energy in the redshift range of 0 0) = 0.080 and σ(wa) = 0.25 in the CPL model. Compared with CMB+BAO+SN, Tianlai can provide tighter constraints in ΛCDM and wCDM, but looser constraints (tighter than CMB+BAO) in CPL, and the combination CMB+BAO+SN+Tianlai gives σ(w) = 0.013, σ(w0) = 0.055, and σ(wa) = 0.13. In addition, it is found that the synergy of FAST (0 © 2021, CC BY.

关键词： Surveys

How can gravitational-wave standard sirens and 21-cm intensity mapping jointly provide a precise late-universe cosmological probe?

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arXiv 2021年

作者： Jin, Shang-Jie Wang, Ling-Feng Wu, Peng-Ju Zhang, Jing-Fei Zhang, Xin Department of Physics College of Sciences Northeastern University Shenyang110819 China MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China

In the next decades, the gravitational-wave (GW) standard siren observations and the neutral hydrogen 21-cm intensity mapping (IM) surveys, as two promising cosmological probes, will play an important role in precisely measuring cosmological parameters. In this work, we make a forecast for cosmological parameter estimation with the synergy between the GW standard siren observations and the 21-cm IM surveys. We choose the Einstein Telescope (ET) and the Taiji observatory as the representatives of the GW detection projects and choose the Square Kilometre Array (SKA) phase I mid-frequency array as the representative of the 21-cm IM experiments. In the simulation of the 21-cm IM data, we assume perfect foreground removal and calibration. We find that the synergy of the GW standard siren observations and the 21-cm IM survey could break the cosmological parameter degeneracies. The joint ET+Taiji+SKA data give σ(H0) = 0.28 km s−1 Mpc−1 in the ΛCDM model, σ(w) = 0.028 in the wCDM model, which are better than the results of Planck+BAO+SNe, and σ(w0) = 0.077 and σ(wa) = 0.295 in the CPL model, which are comparable with the results of Planck+BAO+SNe. In the ΛCDM model, the constraint precision of H0 and Ωm is less than or rather close to 1%, indicating that the magnificent prospects for precision cosmology with these two promising cosmological probes are worth expecting. © 2021, CC BY.

关键词： Surveys

A review of big data technology and its application in cancer care

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Computers in Biology and Medicine 2024年 176卷 108577-108577页

作者： Xiao, Tianyun Kong, Shanshan Zhang, Zichen Hua, Dianbo Liu, Fengchun Hebei Key Laboratory of Data Science and Application North China University of Science and Technology Hebei Tangshan063210 China The Key Laboratory of Engineering Computing in Tangshan City North China University of Science and Technology Hebei Tangshan063210 China College of Science North China University of Science and Technology Hebei Tangshan063210 China Hebei Engineering Research Center for the Intelligentization of Iron Ore Optimization and Ironmaking Raw Materials Preparation Processes North China University of Science and Technology Hebei Tangshan China Tangshan Intelligent Industry and Image Processing Technology Innovation Center North China University of Science and Technology Hebei Tangshan China Beijing Sitairui Cancer Data Analysis Joint Laboratory Beijing101149 China

The development of modern medical devices and information technology has led to a rapid growth in the amount of data available for health protection information, with the concept of medical big data emerging globally, along with significant advances in cancer care relying on data-driven approaches. However, outstanding issues such as fragmented data governance, low-quality data specification, and data lock-in still make sharing challenging. Big data technology provides solutions for managing massive heterogeneous data while combining artificial intelligence (AI) techniques such as machine learning (ML) and deep learning (DL) to better mine the intrinsic connections between data. This paper surveys and organizes recent articles on big data technology and its applications in cancer, dividing them into three different types to outline their primary content and summarize their critical role in assisting cancer care. It then examines the latest research directions in big data technology in cancer and evaluates the current state of development of each type of application. Finally, current challenges and opportunities are discussed, and recommendations are made for the further integration of big data technology into the medical industry in the future. © 2024 Elsevier Ltd

关键词： Big data

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

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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

A new cosmological probe using super-massive black hole shadows

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Chinese Physics C 2020年第5期44卷 119-123页

作者： Jing-Zhao Qi Xin Zhang Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Ministry of Education’s Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern UniversityShenyang 110819China Center for High Energy Physics Peking UniversityBeijing 100080China Center for Gravitation and Cosmology Yangzhou UniversityYangzhou 225009China

We study the prospects of using the low-redshift and high-redshift black hole shadows as new cosmological standard rulers for measuring cosmological *** show that,using the low-redshift observation of the black hole shadow of M87?,the Hubble constant can be independently determined with a precision of about 13%as H0=70±9 km s?1 Mpc?*** high-redshift observations of super-massive black hole shadows may accurately determine a combination of parameters H0 andΩm,and we show by a simple simulation that combining them with the type Ia supernovae observations would give precise measurements of the cosmological parameters.

关键词： black hole shadow cosmological probe standard ruler cosmological parameters the Hubble constant

Quantum controlling and the topological properties of the magnon photo-transport in two-dimensional collinear ferromagnet

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arXiv 2025年

作者： Li, Jun-Cen Du, An College of Sciences Northeastern University Shenyang110004 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University China Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Ministry of Education China

In our work, we study magnon transport induced by light through Aharonov-Casher (AC) effect, including magnon spin photocurrent (MSPC) and magnon energy photocurrent (MEPC). Firstly, we regard the effect of the electric field on the magnon through the AC effect as a perturbation. Then we derived the expressions of MSPC and MEPC in two-dimensional collinear ferromagnetic system. And we apply our theory to the two-dimension ferromagnetic Hexagonal and Kagome lattice. We find that the optical frequency and the relaxation time of the material can be used to control the photo-transport of magnons. In addition, under the condition of low light frequncy and infinite relaxation time, the longitudinal magnon photo-transport is related to the topological property of the magnon system. Copyright © 2025, The Authors. All rights reserved.

关键词： Ferromagnetic materials

Cosmology with fast radio bursts in the era of SKA

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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

Alternating current conductivity and superconducting properties of the holographic effective theory

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arXiv 2022年

作者： Liu, Yan Wang, Xi-Jing Wu, Jian-Pin Zhang, Xin Department of Physics College of Sciences Northeastern University Shenyang110819 China Center for Gravitation and Cosmology College of Physical Science and Technology Yangzhou University Yangzhou225009 China 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 construct a holographic effective superconducting theory by considering a special gauge-axion higher derivative term. The gauge-axion coupling results in the transport behavior similar to the vortex response in the dual boundary field theory leading to non-Drude behavior of alternating current (AC) conductivity at the weak momentum dissipation. With the momentum dissipation increasing, a dip exhibits in the AC conductivity at low frequency. It is thought to be the result of a combination of the strong momentum dissipation and the gauge-axion coupling. In the superconducting phase, this gauge-axion coupling also plays a key role leading to a more evident gap at the low frequency conductivity. In addition, we also study the combined effects of the strength of momentum dissipation and various couplings among the gauge field, axion fields and the complex scalar field. Copyright © 2022, The Authors. All rights reserved.

关键词： Momentum