Measurements of the Hubble constant and cosmic curvature with quasars: ultracompact radio structure and strong gravitational lensing

ABSTRACT Although the Hubble constant H0 and spatial curvature ΩK have been measured with very high precision, they still suffer from some tensions. In this paper, we propose an improved method to combine the observations of ultracompact structure in radio quasars and strong gravitational lensing with quasars acting as background sources to determine H0 and ΩK simultaneously. By applying the distance sum rule to the time-delay measurements of seven strong lensing systems and 120 intermediate-luminosity quasars calibrated as standard rulers, we obtain stringent constraints on the Hubble constant (H0 = 78.3 ± 2.9 km s−1 Mpc−1) and the cosmic curvature (ΩK = 0.49 ± 0.24). On the one hand, in the framework of a flat universe, the measured Hubble constant ($H_0=73.6^{+1.8}_{-1.6} \mathrm{\,km\,s^{-1}\,Mpc^{-1}}$) is strongly consistent with that derived from the local distance ladder, with a precision of 2 per cent. On the other hand, if we use the local H0 measurement as a prior, our results are marginally compatible with zero spatial curvature ($\Omega _K=0.23^{+0.15}_{-0.17}$) and there is no significant deviation from a flat universe. Finally, we also evaluate whether strongly lensed quasars would produce robust constraints on H0 and ΩK in the non-flat and flat Λ cold dark matter model, if the compact radio structure measurements are available from very long baseline interferometry observations.

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Updated reduced CMB data and constraints on cosmological parameters

International Journal of Modern Physics D ◽

10.1142/s0218271815500716 ◽

2015 ◽

Vol 24 (10) ◽

pp. 1550071 ◽

Cited By ~ 3

Author(s):

Rong-Gen Cai ◽

Zong-Kuan Guo ◽

Bo Tang

Keyword(s):

Dark Energy ◽

Equation Of State ◽

Confidence Level ◽

Cosmological Parameters ◽

Hubble Constant ◽

Spatial Curvature ◽

Λcdm Model ◽

The One

We obtain the reduced CMB data {lA, R, z∗} from WMAP9, WMAP9+BKP, Planck+WP and Planck+WP+BKP for the ΛCDM and wCDM models with or without spatial curvature. We then use these reduced CMB data in combination with low-redshift observations to put constraints on cosmological parameters. We find that including BKP results in a higher value of the Hubble constant especially when the equation of state (EOS) of dark energy and curvature are allowed to vary. For the ΛCDM model with curvature, the estimate of the Hubble constant with Planck+WP+Lensing is inconsistent with the one derived from Planck+WP+BKP at about 1.2σ confidence level (CL).

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HOLISMOKES

Astronomy and Astrophysics ◽

10.1051/0004-6361/202037757 ◽

2020 ◽

Vol 644 ◽

pp. A162

Author(s):

S. H. Suyu ◽

S. Huber ◽

R. Cañameras ◽

M. Kromer ◽

S. Schuldt ◽

...

Keyword(s):

Time Delay ◽

Gravitational Lensing ◽

Early Phase ◽

Rest Frame ◽

Hubble Constant ◽

Angular Diameter ◽

Strong Gravitational Lensing ◽

Space And Time ◽

Precise Time

We present the HOLISMOKES programme on strong gravitational lensing of supernovae (SNe) as a probe of SN physics and cosmology. We investigate the effects of microlensing on early-phase SN Ia spectra using four different SN explosion models. We find that distortions of SN Ia spectra due to microlensing are typically negligible within ten rest-frame days after a SN explosion (< 1% distortion within the 1σ spread and ≲10% distortion within the 2σ spread). This shows the great prospects of using lensed SNe Ia to obtain intrinsic early-phase SN spectra for deciphering SN Ia progenitors. As a demonstration of the usefulness of lensed SNe Ia for cosmology, we simulate a sample of mock lensed SN Ia systems that are expected to have accurate and precise time-delay measurements in the era of the Rubin Observatory Legacy Survey of Space and Time (LSST). Adopting realistic yet conservative uncertainties on their time-delay distances and lens angular diameter distances, of 6.6% and 5%, respectively, we find that a sample of 20 lensed SNe Ia would allow us to constrain the Hubble constant (H0) with 1.3% uncertainty in the flat ΛCDM cosmology. We find a similar constraint on H0 in an open ΛCDM cosmology, while the constraint degrades to 3% in a flat wCDM cosmology. We anticipate lensed SNe to be an independent and powerful probe of SN physics and cosmology in the upcoming LSST era.

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STRONG GRAVITATIONAL LENSING AND ITS COSMIC CONSTRAINTS

Modern Physics Letters A ◽

10.1142/s0217732313500570 ◽

2013 ◽

Vol 28 (14) ◽

pp. 1350057 ◽

Cited By ~ 7

Author(s):

NANNAN WANG ◽

LIXIN XU

Keyword(s):

Cosmological Model ◽

Gravitational Lensing ◽

Velocity Dispersion ◽

Model Space ◽

Data Sets ◽

Spatial Curvature ◽

Strong Gravitational Lensing ◽

Strong Lensing ◽

Λcdm Model ◽

Stellar Velocity

In this paper, we propose a new method to use the strong lensing data sets to constrain a cosmological model. By taking the ratio [Formula: see text] as cosmic observations, one can completely eliminate the uncertainty caused by the relation σSIS= fEσ0which characterizes the relation between the stellar velocity dispersion σ0and the velocity dispersion σSIS. Via our method, a relative tight constraint to the cosmological model space can be obtained, for the spatially flat ΛCDM model as an example [Formula: see text] in 3σ regions. And by using this method, one can also probe the nature of dark energy and the spatial curvature of our Universe.

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Cosmological Parameter Survey Using the Gravitational Lensing Method

Publications of the Astronomical Society of Australia ◽

10.1071/as01022 ◽

2001 ◽

Vol 18 (2) ◽

pp. 201-206 ◽

Cited By ~ 2

Author(s):

Premana W. Premadi ◽

Hugo Martel ◽

Richard Matzner ◽

Toshifumi Futamase

Keyword(s):

Gravitational Lensing ◽

Light Propagation ◽

Cold Dark Matter ◽

Cosmological Parameters ◽

Angular Size ◽

Hubble Constant ◽

Density Parameter ◽

Multiple Imaging ◽

Light Rays ◽

Insight Into

AbstractUsing a multiple-lens plane algorithm, we study light propagation in inhomogeneous universes for 43 different COBE-normalized Cold Dark Matter models, with various values of the density parameter Ω0, cosmological constant λ0, Hubble constant H0, and rms density fluctuation σ8.We performed a total of 3798 experiments, each experiment consisting of propagating a square beam of angular size 21.9″ 21.9″ composed of 116 281 light rays from the observer up to redshift z = 3. These experiments provide statistics of the magnification, shear, and multiple imaging of distant sources. The results of these experiments might be compared with observations, and eventually help constrain the possible values of the cosmological parameters. Additionally, they provide insight into the gravitational lensing process and its complex relationship with the various cosmological parameters.

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Test of the cosmic distance duality relation for arbitrary spatial curvature

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab124 ◽

2021 ◽

Vol 502 (3) ◽

pp. 3500-3509

Author(s):

Jin Qin ◽

Fulvio Melia ◽

Tong-Jie Zhang

Keyword(s):

Gravitational Lensing ◽

High Redshift ◽

Duality Relation ◽

Spatial Curvature ◽

Hubble Diagram ◽

Sis Model ◽

Strong Gravitational Lensing ◽

Best Fitting ◽

Model Independent ◽

The Universe

ABSTRACT The cosmic distance duality relation (CDDR), η(z) = (1 + z)2dA(z)/dL(z) = 1, is one of the most fundamental and crucial formulae in cosmology. This relation couples the luminosity and angular diameter distances, two of the most often used measures of structure in the Universe. We here propose a new model-independent method to test this relation, using strong gravitational lensing (SGL) and the high-redshift quasar Hubble diagram reconstructed with a Bézier parametric fit. We carry out this test without pre-assuming a zero spatial curvature, adopting instead the value ΩK = 0.001 ± 0.002 optimized by Planck in order to improve the reliability of our result. We parametrize the CDDR using η(z) = 1 + η0z, 1 + η1z + η2z2, and 1 + η3z/(1 + z), and consider both the SIS and non-SIS lens models for the strong lensing. Our best-fitting results are: $\eta _0=-0.021^{+0.068}_{-0.048}$, $\eta _1=-0.404^{+0.123}_{-0.090}$, $\eta _2=0.106^{+0.028}_{-0.034}$, and $\eta _3=-0.507^{+0.193}_{-0.133}$ for the SIS model, and $\eta _0=-0.109^{+0.044}_{-0.031}$ for the non-SIS model. The measured η(z), based on the Planck parameter ΩK, is essentially consistent with the value (=1) expected if the CDDR were fully respected. For the sake of comparison, we also carry out the test for other values of ΩK, but find that deviations of spatial flatness beyond the Planck optimization are in even greater tension with the CDDR. Future measurements of SGL may improve the statistics and alter this result but, as of now, we conclude that the CDDR favours a flat Universe.

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Probing Quantum Gravity Through Strong Gravitational Lensing

10.20944/preprints201712.0093.v1 ◽

2017 ◽

Author(s):

Stuart Marongwe

Keyword(s):

Dark Matter ◽

Gravitational Field ◽

Quantum Gravity ◽

Gravitational Lensing ◽

Cold Dark Matter ◽

Space Time ◽

Radius Of Curvature ◽

Space Telescope ◽

Strong Gravitational Lensing ◽

The Core

We report the use of Einstein rings to reveal the quantized and dynamical states of space-time in a region of impressed gravitational field as predicted by the Nexus Paradigm of quantum gravity. This in turn reveals the orbital speeds of objects found therein and the radius of curvature of the quantized space-time. Similarities between the Nexus graviton and the singular isothermal sphere (SIS) in the Cold Dark Matter (CDM) paradigm are highlighted. However unlike the singular isothermal sphere, the Nexus graviton does not contain singularities or divergent integrals. This solves the core cusp problem. In this work, data from a sample of fifteen Einstein rings published on the Cfa-Arizona Space Telescope Lens Survey (CASTLES) website is used to probe the quantized properties of space-time.

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The graviton Compton mass as Dark Energy

Revista Mexicana de Física ◽

10.31349/revmexfis.67.4.040703 ◽

2021 ◽

Vol 67 (4 Jul-Aug) ◽

Author(s):

Tonatiuh Matos ◽

L. Parrilla

Keyword(s):

Dark Energy ◽

Hubble Constant ◽

Accelerated Expansion ◽

Coincidence Problem ◽

Natural Explanation ◽

Observable Universe ◽

Local Distance ◽

Free Constant ◽

The One ◽

The Universe

One of the greatest challenges of science is to understand the current accelerated expansion of the Universe. In this work we show that by considering the quantum nature of the gravitational field, its wavelength can be associated to an effective Compton mass. We propose that this mass can be interpreted as dark energy, with a Compton wavelength given by the size of the observable Universe, implying that the dark energy varies depending on this size. If we do so, we find that: 1.- Even without any free constant for dark energy, the evolution of the Hubble parameter is exactly the same as for the LCDM model, so this model has the same predictions as LCDM. 2.- The density rate of the dark energy is ΩΛ = 0.69 which is a very similar value as the one found by the Planck satellite ΩΛ = 0.684. 3.- The dark energy has this value because it corresponds to the actual size of the radius of the Universe, thus the coincidence problem has a very natural explanation. 4.- It is possible to find also a natural explanation to why observations inferred from the local distance ladder find the value H0 = 73 km/s/Mpc for the Hubble constant, we show that if we take the variability of the dark energy into account they should measure H0 = 67.3 km/s/Mpc as well. 5.- In this model the inflationary period contains a natural successful graceful exit.

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New constraint of the Hubble constant by proper motions of radio components observed in AGN twin-jets

Research in Astronomy and Astrophysics ◽

10.1088/1674-4527/21/10/261 ◽

2021 ◽

Vol 21 (10) ◽

pp. 261

Author(s):

Wei-Jian Lu ◽

Yi-Ping Qin

Keyword(s):

Dark Matter ◽

Cold Dark Matter ◽

Hubble Constant ◽

Proper Motions ◽

Microwave Background ◽

Background Data ◽

Local Distance ◽

Twin Jets ◽

Real Value ◽

Cosmic Microwave Background Data

Abstract As the advent of precision cosmology, the Hubble constant (H 0) inferred from the Lambda Cold Dark Matter fit to the Cosmic Microwave Background data is increasingly in tension with the measurements from the local distance ladder. To approach its real value, we need more independent methods to measure, or to make constraint of, the Hubble constant. In this paper, we apply a plain method, which is merely based on the Friedman-Lemaître-Robertson-Walker cosmology together with geometrical relations, to constrain the Hubble constant by proper motions of radio components observed in AGN twin-jets. Under the assumption that the ultimate ejection strengths in both sides of the twin-jet concerned are intrinsically the same, we obtain a lower limit of H 0,min = 51.5 ± 2.3 km s−1 Mpc−1 from the measured maximum proper motions of the radio components observed in the twin-jet of NGC 1052.

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