The cosmological constant is one of the most pressing problems in modern physics. We address this issue from an emergent gravity standpoint, by using an analogue gravity model. Indeed, the dynamics of the emergent metric in a Bose-Einstein condensate can be described by a Poisson-like equation with a vacuum source term reminiscent of a cosmological constant. The direct computation of this term shows that in emergent gravity scenarios this constant may be naturally much smaller than the naive ground-state energy of the emergent effective field theory. This suggests that a proper computation of the cosmological constant would require a detailed understanding about how Einstein equations emerge from the full microscopic quantum theory. In this light, the cosmological constant appears as a decisive test bench for any quantum or emergent gravity scenario.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevLett.108.071101 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Effects of the Quantum Vacuum at a Cosmic Scale and of Dark Energy.
Entropy (Basel)
November 2024
Departamento de Física, Universidad de Cantabria, 39005 Santander, Spain.
The Einstein equation in a semiclassical approximation is applied to a spherical region of the universe, with the stress-energy tensor consisting of the mass density and pressure of the ΛCDM cosmological model plus an additional contribution due to the quantum vacuum. Expanding the equation in powers of Newton constant G, the vacuum contributes to second order. The result is that at least a part of the acceleration in the expansion of the universe may be due to the quantum vacuum fluctuations.
View Article and Find Full Text PDFSuppression without Thawing: Constraining Structure Formation and Dark Energy with Galaxy Clustering.
Phys Rev Lett
December 2024
Department of Astronomy, Cornell University, Ithaca, New York 14853, USA.
We present a new perturbative full-shape analysis of BOSS galaxy clustering data, including the full combination of the galaxy power spectrum and bispectrum multipoles, baryon acoustic oscillations, and cross-correlations with the gravitational lensing of cosmic microwave background measured from Planck. Assuming the ΛCDM model, we constrain the matter density fraction Ω_{m}=0.3138±0.
View Article and Find Full Text PDFSpinning Black Binaries in de Sitter Space.
Phys Rev Lett
November 2024
Maryland Center for Fundamental Physics, University of Maryland, College Park, Maryland 20742, USA.
We numerically construct stationary, rotating black binaries in general relativity with a positive cosmological constant. We consider identical black holes with either aligned or anti-aligned spins. Both cases have less entropy than the corresponding single Kerr-Schwarzschild-de Sitter black hole with the same total angular momentum and cosmological horizon entropy.
View Article and Find Full Text PDFOn the Fourier Analysis of the Einstein-Klein-Gordon System: Growth and Decay of the Fourier Constants.
Ann Henri Poincare
December 2023
Mathematisches Institut, Westfälische Wilhelms-Universität Münster, Einsteinstrasse 62, 48149 Münster, Germany.
We consider the -dimensional Einstein equations with negative cosmological constant coupled to a spherically symmetric, massless scalar field and study perturbations around the anti-de Sitter spacetime. We derive the resonant systems, pick out vanishing secular terms and discuss issues related to small divisors. Most importantly, we rigorously establish (sharp, in most of the cases) asymptotic behaviour for all the interaction coefficients.
View Article and Find Full Text PDFExplicit construction of Penrose diagrams for black hole to white hole transition with spacelike thin shells.
Sci Rep
November 2024
Center for Cosmological Constant Problem, Extreme Physics Institute, Pusan National University, Busan, 46241, Republic of Korea.
In this article, we explicitly construct the coordinates associated with the Penrose diagram in spacetimes connected via a spacelike thin shell in the following two examples: the generalized black-to-white hole bounce with mass difference and the Schwarzschild-to-de Sitter transition. We point out the issue of the first junction condition in the Penrose diagram constructed by cutting and pasting analytically known metrics with spherical symmetry by a static spacelike thin shell. With the goal of a global conformal coordinate chart associated with the corresponding Penrose diagram without discontinuity at the thin shell, we give a procedure consisting of three conformal transformations that serve different purposes.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!