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Constraining the hubble constant to a precision of about 1% using multi-band dark standard siren detections

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Science China(Physics,Mechanics & Astronomy) 2022年第5期65卷 114-140页

作者： Liang-Gui Zhu Ling-Hua Xie Yi-Ming Hu Shuai Liu En-Kun Li Nicola R.Napolitano Bai-Tian Tang Jian-Dong Zhang Jianwei Mei School of Physics and Astronomy Sun Yat-sen University(Zhuhai Campus)Zhuhai 519082China MOE Key Laboratory of Tian Qin Mission Tian Qin Research Center for Gravitational PhysicsFrontiers Science Center for Tian QinCNSA Research Center for Gravitational WavesSun Yat-sen University(Zhuhai Campus)Zhuhai 519082China

Gravitational wave signal from the inspiral of stellar-mass binary black hole can be used as standard sirens to perform cosmological *** inspiral covers a wide range of frequency bands,from the millihertz band to the audio-band,allowing for detections by both space-borne and ground-based gravitational wave *** this work,we conduct a comprehensive study on the ability to constrain the hubble constant using the dark standard sirens,or gravitational wave events that lack electromagnetic *** acquire the redshift information,we weight the galaxies within the localization error box with photometric information from several bands and use them as a proxy for the binary black hole *** discover that Tian Qin is expected to constrain the hubble constant to a precision of roughly 30%through detections of 10 gravitational wave events;in the most optimistic case,the hubble constant can be constrained to a precision ofhubble constant to within 5%*** is worth highlighting that the multi-band network of Tian Qin and Einstein Telescope is capable of constraining the hubble constant to a precision of about 1%.We conclude that inferring the hubble constant without bias from photo-z galaxy catalog is achievable,and we also demonstrate self-consistency using the P-P *** the other hand,high-quality spectroscopic redshift information is crucial for improving the estimation precision of hubble constant.

关键词： gravitational wave standard siren hubble constant stellar-mass binary black hole photometric luminosity multi-band gravitational wave detection

Possible bias of the constraints on the hubble constant owing to the quasi-Gaussian distribution of DM_(IGM)in fast radio bursts

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Chinese Physics C 2024年第7期48卷 211-220页

作者：陈贵垚李昕 Department of Physics Chongqing UniversityChongqing 401331China Chongqing Key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China

Fast radio bursts(FRBs)are useful cosmological probes with numerous applications in *** distribution of the dispersion measurement contribution from the intergalactic medium is a key issue.A quasi-Gaussian distribution has been used to replace the traditional Gaussian distribution,yielding promising ***,this study suggests that there may be additional challenges in its *** used 35 well-localized FRBs to constrain the hubble constant H_(0)along with two FRB-related parameters,yielding H_(0)=■The best-fitting hubble constant H_(0)is smaller than the value obtained from the Cosmic Microwave Background(CMB),which may be caused by the small sample size of current FRB *** Carlo simulations indicate that a set of 100 simulated FRBs provides a more precise fitting result for the hubble ***,the precision of the hubble constant does not improve when further enlarging the FRB *** simulations reveal a systematic deviation in the fitting results of H_(0),attributed to the quasi-Gaussian distribution of the dispersion measure in the intergalactic *** this,the results remain reliable within 1σuncertainty,assuming that a sufficient number of FRB data points are available.

关键词： fast radio bursts hubble constant cosmological parameters

Measurement of hubble constant: were differences in secondary distance indicators apparent as early as the HST Key Project?

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Research in Astronomy and Astrophysics 2021年第3期21卷 97-106页

作者： Rahul Kumar Thakur Shashikant Gupta Rahul Nigam PK Thiruvikraman Birla Institute of Technology&Science Pilani-Hyderabad CampusIndia G D Goenka University GurgaonHaryana122103India

Different measurements of the hubble constant(H_(0))are not consistent,and a tension between the CMB based methods and cosmic distance ladder based methods has been *** from various distance based methods are also *** aggravate the problem,the same cosmological probe(TypeⅠa SNe for instance)calibrated through different methods also provides different values of H_(0).We compare various distance ladder based methods through the already available unique data obtained from the hubble Space Telescope(HST).Our analysis is based on parametric(t-test)as well as non-parametric statistical methods such as the Mann-Whitney U test and Kolmogorov-Smirnov *** results show that different methods provide different values of H_(0) and the differences are statistically *** biases in the calibration would not account for these differences as the data have been taken from a single telescope with a common calibration *** unknown physical effects or issues with the empirical relations of distance measurement from different probes could give rise to these differences.

关键词： Cosmology Supernovae hubble constant

The Source of Tension in the Measurements of the hubble constant

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International Journal of Astronomy and Astrophysics 2022年第3期12卷 273-280页

作者： Naser Mostaghel Department of Civil Engineering University of Toledo Toledo USA

Through an analytical approach, we show that the hubble constant is not unique and has two distinct values. The first of these values is consistent with the measurements by Riess et al., while the second value is consistent with the measurements by the Planck Collaboration. This is a new alternative approach that does not depend on the standard ΛCDM model and its constraints. Our analysis shows that the tension is due to a geometric mismatch in the comparison of the measurements which is equal to the temporal diameter of the surface of last scattering. Since the calculated values are essentially identical to the corresponding measured values, we conclude that the non-congruency of the ending point of the Riess et al. measurement and the starting point of the Planck Collaboration measurement, on the surface of last scattering, is the source of tension in the measurements. Further, the surprising consistency of the calculated values of the hubble constant with the corresponding measured values confirms both the extreme fidelity of the measurements and the validity of the proposed approach.

关键词： Cosmology hubble constant Cosmology: Observations

Relativistic Quantitative Determination of the “Mysterious” Differences in the hubble constant

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Natural Science 2021年第1期13卷 1-7页

作者： Ernst Karl Kunst Kö nigswinter Germany

This paper discusses the “hubble constant measurement—mystery”. Independent measurements of this cosmic parameter, referred to as H0 in abbreviated form, have all led to different values, with the highest value ≈ 74 km·s-1·Mpc-1 and the lowest ≈ 67 km·s-1·Mpc-1, where km denotes kilometer, s second and Mpc-1 megaparsec. These measurements have mainly been obtained with space telescopes. Apparently, up to now there was no way to explain the differences. However, previously published studies seem to regard the problem of the different measurement results for H0 [1, 2]. I have shown that due to a symmetrical

关键词： hubble constant Different Measurement Results Earthbound and Space-Telescopes Different Orbits Different hubble constants Symmetric Special Relativistic Origin

The Derivation of the Cosmic Microwave Background Radiation Peak Spectral Radiance, Planck Time, and the hubble constant from the Neutron and Hydrogen

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Journal of Modern Physics 2016年第6期7卷 573-586页

作者： Donald William Chakeres Vola Andrianarijaona Department of Radiology The Ohio State University Columbus OH USA Department of Physics & Engineering Pacific Union College Angwin CA USA

Purpose: The cosmic microwave background radiation, CMB, is fundamental to observational cosmology, and is believed to be a remnant from the Big Bang. The CMB, Planck time, tP, and the hubble constant, H0, are important cosmologic constants. The goal is to accurately derive and demonstrate the inter-relationships of the CMB peak spectral radiance frequency, tP, and H0 from neutron and hydrogen quantum data only. Methods: The harmonic neutron hypothesis, HNH, evaluates physical phenomena within a finite consecutive integer and exponential power law harmonic fraction series that are scaled by a fundamental frequency of the neutron as the exponent base. The CMB and the H0 are derived from a previously published method used to derive tP. Their associated integer exponents are respectively +1/2, −3/4, and −128/35. Results: Precise mathematical relationships of these three constants are demonstrated. All of the derived values are within their known observational values. The derived and known values are: νCMB, 160.041737 (06) × 109 Hz, ~160 × 109 Hz;2.72519 K, 2.72548 ± 0.00057 K, H0 2.29726666 (11) × 10−18 s−1, ~2.3 × 10−18 s−1;and tP 5.3911418 (3) × 10−44 s, 5.39106 (32) × 10−44 s. Conclusion: The cosmic fundamental constants tP, H0, and CMB are mathematically inter-related constants all defined by gravity. They are also directly derivable from the quantum properties of the neutron and hydrogen within a harmonic power law.

关键词： Cosmic Microwave Background Radiation Neutron Fundamental Physical constants Unification Models Hydrogen Planck Time hubble constant

Relativistic Supernova Blast Waves Exhibit Properties of Gravitational Lenses and the hubble constant

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Journal of High Energy Physics, Gravitation and Cosmology 2023年第4期9卷 1237-1258页

作者： Paul Marko Electromagnetic Design Group Deerfield Beach USA

Simulations based on Supernova (SN) observations predict several galactic SN explosions (SNe) can occur every century. Unlike SNes within the Interstellar Medium (ISM) where ambient gas generally absorbs blast waves within a million years, SNes occurring in a rarified environment outside of the ISM generate blast waves which remain in a relativistic free expansion phase for more extended periods. The SN blast wave forms an expanding spherical shell and when multiple blast waves intersect, the overlapping region naturally takes the form of a ring, an arc, or an Einstein Cross structure. The analysis shows the relativistic plasma establishes a medium with permeability which drives the index of refraction greater than 1. As a result, when a shock discontinuity forms in the overlapping region, light is reflected from the host galaxy which exposes the intersecting blast wave regions. The expanding shells are shown to induce an achromatic redshift to the reflected light consistent with those measured for gravitational lenses. Further, it is shown that a hubble equation for a blast wave around the Milky Way Galaxy can be parameterized to approximate measured redshifts over a wide range of distances.

关键词： Supernova Plasma Gravitational Lens Einstein Cross hubble constant

The hubble constant Problem and the Solution by Gravitation in Flat Space-Time

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Journal of Modern Physics 2020年第2期11卷 214-220页

作者： Walter Petry Mathematical Institute of the University Düsseldorf DüsseldorfGermany

General Relativity implies an expanding Universe from a singularity, the so-called Big Bang. The rate of expansion is the hubble constant. There are two major ways of measuring the expansion of the Universe: through the cosmic distance ladder and through looking at the signals originated from the beginning of the Universe. These two methods give quite different results for the hubble constant. Hence, the Universe doesn’t expand. The solution to this problem is the theory of gravitation in flat space-time where space isn’t expanding. All the results of gravitation for weak fields of this theory agree with those of General Relativity to measurable accuracy whereas at the beginning of the Universe the results of both theories are quite different, i.e. no singularity by gravitation in flat space-time and non-expanding universe, and a Big Bang (singularity) by General Relativity.

关键词： Gravitation in Flat Space-Time Cosmological Models hubble constant No Big Bang No Singularity Non-Expanding Universe

Predicting High Precision hubble constant Determinations Based on a New Theoretical Relationship between CMB Temperature and H0

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Journal of Modern Physics 2024年第11期15卷 1708-1716页

作者： Eugene Terry Tatum Espen Gaarder Haug Stéphane Wojnow Bowling Green KY USA Norwegian University of Life Sciences s Norway Limoges France

Based on considerable progress made in understanding the Cosmic Microwave Background (CMB) temperature from a deep theoretical perspective, this paper demonstrates a useful and simple relationship between the CMB temperature and the hubble constant. This allows us to predict the hubble constant with much higher precision than before by using the CMB temperature. This is of great importance, since it will lead to much higher precision in various global parameters of the cosmos, such as the hubble radius and the age of the universe. We have improved uncertainty in the hubble constant all the way down to 66.8712 ± 0.0019 km/s/Mpc based on data from one of the most recent CMB studies. Previous studies based on other methods have rarely reported an uncertainty much less than approximately ±1 km/s/Mpc for the hubble constant. Our deeper understanding of the CMB and its relation to H0seems to be opening a new era of high-precision cosmology, which may well be the key to solving the hubble tension, as alluded to herein. Naturally, our results should also be scrutinized by other researchers over time, but we believe that, even at this stage, this deeper understanding of the CMB deserves attention from the research community.

关键词： hubble constant CMB Planck Temperature Upsilon constant