Large-scale structure with superhorizon isocurvature dark energy

Abstract

The standard cosmological model assumes a homogeneous and isotropic universe as the background spacetime on large scales called the cosmological principle. However, some observations suggest the possibility of an inhomogeneous and anisotropic universe at large scales. In this paper, we investigate a model of the universe with random inhomogeneities and anisotropies on very large scales, motivated by the supercurvature dark energy model in Nan et al. [Phys. Rev. D 99, 103512 (2019)]. In this model, the authors introduced a scalar field with $\mathcal{O}(1)$ inhomogeneities on a scale sufficiently larger than the current horizon scale (superhorizon scale), and the potential energy of the scalar field explains the accelerating expansion, with slight deviations from the cosmological principle. We aim at clarifying the theoretical prediction on the large-scale structure (LSS) of the matter component in this model. Based on the work on the superhorizon scale fluctuations (superhorizon mode) presented in Nan and Yamamoto [Phys. Rev. D 105, 063518 (2022)], we derive the equations that the perturbative components to the LSS obey as a generalization of the cosmological perturbations theory, which is solved to find the influence of the dark energy inhomogeneities on the formation of the LSS. Finally, we show that the model can be consistent with observations by comparing the ${\sigma }_8$ predicted by the numerical solution of the model with the ${\sigma }_8$ indicated by observations such as Planck and SDSS.

arXiv comment24 pages, 4 figures

References in corpus (56)

• Planck 2013 results. XVI. Cosmological parameters
• Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Parameter Results
• Exploring the Expansion History of the Universe
• Accelerating Universes with Scaling Dark Matter
• The Cosmic Linear Anisotropy Solving System (CLASS) II: Approximation schemes
• String Axiverse
• KiDS-1000 Cosmology: Cosmic shear constraints and comparison between two point statistics
• Distance and de Sitter Conjectures on the Swampland
• Cosmology from cosmic shear power spectra with Subaru Hyper Suprime-Cam first-year data
• The String Landscape and the Swampland
• Indications of a spatial variation of the fine structure constant
• Bounds on Slow Roll and the de Sitter Swampland
• De Sitter Space and the Swampland
• CMB Anomalies after Planck
• Hemispherical power asymmetry in the three-year Wilkinson Microwave Anisotropy Probe sky maps
• New Extraction of the Cosmic Birefringence from the Planck 2018 Polarization Data
• A Test of the Cosmological Principle with Quasars
• Planck 2013 results. XXVII. Doppler boosting of the CMB: Eppur si muove
• Super-Sample Covariance in Simulations
• Arbitrating the $S_8$ discrepancy with growth rate measurements from Redshift-Space Distortions
• Probing cosmic isotropy with a new X-ray galaxy cluster sample through the $L_{\text{X}}-T$ scaling relation
• The Weak Lensing Signal and the Clustering of BOSS Galaxies II: Astrophysical and Cosmological Constraints
• Separate Universe Simulations
• Alleviating the $H_0$ and ${\sigma }_8$ anomalies with a decaying dark matter model
• Cosmological implications of the anisotropy of ten galaxy cluster scaling relations
• Hints of FLRW Breakdown from Supernovae
• Constraints on cosmic hemispherical power anomalies from quasars
• Chameleon dark energy can resolve the Hubble tension
• On Larger $H_0$ Values in the CMB Dipole Direction
• Detection of isotropic cosmic birefringence and its implications for axion-like particles including dark energy
• Internal Robustness of Growth Rate data
• Super-Sample Signal
• $H_0$ Tension, Swampland Conjectures and the Epoch of Fading Dark Matter
• Linear response to long wavelength fluctuations using curvature simulations
• Testing Dark energy models in the light of ${\sigma }_8$ tension
• Current Constraints on Anisotropic and Isotropic Dark Energy Models
• Covariance of CMB anomalies
• Bulk viscous embedded hybrid dark energy models
• Probing Dark Energy in The scope of Bianchi type I Spacetime
• The impact of large-scale tides on cosmological distortions via redshift-space power spectrum
• Viscous Dark Energy In Bianchi Type V Space-Time
• Dark Energy Cosmological Models with General forms of Scale Factor
• Planck intermediate results. LVI. Detection of the CMB dipole through modulation of the thermal Sunyaev-Zeldovich effect: Eppur si muove II
• Bianchi-V string cosmological model and late time acceleration
• Testing the Dipole Modulation Model in CMBR
• Anisotropic separate universe simulations
• Dipole Modulation of Cosmic Microwave Background Temperature and Polarization
• CMASS galaxy sample and the ontological status of the cosmological principle
• Nonlinear spherical perturbations in Quintessence Models of Dark Energy
• Super-sample tidal modes on the celestial sphere
• Quintessential Isocurvature in Separate Universe Simulations
• Tachyonic vs Quintessence dark energy: linear perturbations and CMB data
• Measuring Cosmological Parameters with the SDSS QSO Spatial Power Spectrum Analysis to Test the Cosmological Principle
• Large-scale inhomogeneity of dark energy produced in the ancestor vacuum
• Non-linear spherical collapse in tachyon models, and a comparison of collapse in tachyon and quintessence models of dark energy
• Dark energy model with very large-scale inhomogeneity