Unimodular Theory of Gravity in Light of the Latest Cosmological Data

Abstract

The unimodular theory of gravity is an alternative perspective to traditional Einstein's general relativity and opens new possibilities for exploring its implications in cosmology. In this paper, we investigate the unimodular gravity (UG) with the latest cosmological data from the Pantheon sample of Type Ia supernovae (SN), Baryon Acoustic Oscillations (BAO), and the observational H(z) data from Differential Age method (DA). We consider a model consisting of a generalized cosmological constant with radiation and dark matter. The considered theory respects only unimodular coordinate transformations. We fit our model with low-redshift data from SN and DA and determine the value of parameter $\xi$ of the theory. We find the best-fit value of parameter $\xi =6.23\pm 0.5$; which deviates from 6, for which the theory becomes the standard general theory of relativity. We further study the Hubble constant problem by combining the SN and DA data with BAO data. We observe deviation in the value of $H_0$ from the standard $\Lambda$CDM model. We obtain $H_0$ as $70.7 \pm 4.1 \ \mbox{Km s}^{-1} \mbox{Mpc} ^{-1}$ and $69.24 \pm 0.90 \ \mbox{Km s}^{-1} \mbox{Mpc} ^{-1}$ from supernovae data and BAO data, respectively in unimodular gravity. Combining the BAO data with SN+DA data set, we obtain $H_0$ as $70.57 \pm 0.56 \ \mbox{Km s}^{-1} \mbox{Mpc} ^{-1}$.

arXiv comment18 pages, 4 figures

References in corpus (46)

• emcee: The MCMC Hammer
• Dynamics of dark energy
• The Cosmological Constant and Dark Energy
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmological analysis of the DR12 galaxy sample
• The Complete Light-curve Sample of Spectroscopically Confirmed Type Ia Supernovae from Pan-STARRS1 and Cosmological Constraints from The Combined Pantheon Sample
• The Cosmological Constant
• A Comprehensive Measurement of the Local Value of the Hubble Constant with 1 km/s/Mpc Uncertainty from the Hubble Space Telescope and the SH0ES Team
• Baryonic Features in the Matter Transfer Function
• A 2.4% Determination of the Local Value of the Hubble Constant
• In the Realm of the Hubble tension $-$ a Review of Solutions
• The Clustering of the SDSS DR7 Main Galaxy Sample I: A 4 per cent Distance Measure at z=0.15
• Planck 2018 results. I. Overview and the cosmological legacy of Planck
• Constraints on the redshift dependence of the dark energy potential
• A 6% measurement of the Hubble parameter at $z\sim 0.45$: direct evidence of the epoch of cosmic re-acceleration
• Cosmic Chronometers: Constraining the Equation of State of Dark Energy. I: H(z) Measurements
• Early Dark Energy Can Resolve The Hubble Tension
• Raising the bar: new constraints on the Hubble parameter with cosmic chronometers at z$\sim$2
• Improved constraints on the expansion rate of the Universe up to z~1.1 from the spectroscopic evolution of cosmic chronometers
• Constraining Cosmological Parameters Based on Relative Galaxy Ages
• Small Scale Cosmological Perturbations: An Analytic Approach
• Age-dating Luminous Red Galaxies observed with the Southern African Large Telescope
• Constraints on the equation of state of dark energy and the Hubble constant from stellar ages and the CMB
• Baryon acoustic oscillations from the cross-correlation of Ly$\alpha$ absorption and quasars in eBOSS DR14
• The clustering of the SDSS-IV extended Baryon Oscillation Spectroscopic Survey DR14 quasar sample: a tomographic measurement of cosmic structure growth and expansion rate based on optimal redshift weights
• Distance Priors from Planck Final Release
• On the use of the local prior on the absolute magnitude of Type Ia supernovae in cosmological inference
• The quantization of unimodular gravity and the cosmological constant problem
• Galileon Gravity in Light of ISW, CMB, BAO and $H_0$ data
• The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations at redshift of 0.72 with the DR14 Luminous Red Galaxy Sample
• Model independent $H(z)$ reconstruction using the cosmic inverse distance ladder
• Can one tell Einstein's unimodular theory from Einstein's general relativity?
• Unimodular relativity and cosmological constant
• Chameleon dark energy can resolve the Hubble tension
• Can Conformally Coupled Modified Gravity Solve The Hubble Tension?
• Cosmological Perturbations in Unimodular Gravity
• Inflationary cosmology in unimodular $F(T)$ gravity
• Unimodular cosmology and the weight of energy
• Unimodular-Mimetic Cosmology
• Unimodular $f(R,T)$ Gravity
• Unimodular Mimetic $F(R)$ Inflation
• Cosmological Implications of Unimodular Gravity
• Testing Unimodular Gravity
• Hubble constant and sound horizon from the late-time Universe
• Unimodular Gravity Traversable Wormholes
• Unimodular Constraint on global scale Invariance
• A reconstruction method for anisotropic universes in unimodular $F(R)$-gravity

Cited by in corpus (1)

• Seven hints that early-time new physics alone is not sufficient to solve the Hubble tension