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Related Experiment Video

Updated: Jun 26, 2026

Scattering And Absorption of Light in Planetary Regoliths

Scattering And Absorption of Light in Planetary Regoliths

Published on: July 1, 2019

Can we avoid dark energy?

James P Zibin¹, Adam Moss, Douglas Scott

¹Department of Physics & Astronomy, University of British Columbia, Vancouver, BC, V6T 1Z1 Canada.

Physical Review Letters

|December 31, 2008

Summary

Cosmological void models offer an alternative to dark energy but face challenges. While fitting cosmic microwave background and supernova data, they require fine-tuning or an unacceptably low Hubble rate, limiting their viability.

Area of Science:

Cosmology
General Relativity
Astrophysics

Background:

The standard cosmological model (Lambda-CDM) explains cosmic acceleration via dark energy.
Alternative theories, including modified gravity and large-scale structures like voids, are being explored.
A nonlinear void model proposes our location near the center of a large void as an alternative explanation for cosmic acceleration.

Purpose of the Study:

To investigate the viability of a large, nonlinear void model as an alternative to dark energy.
To test the void model against observational data, including cosmic microwave background and supernova surveys.
To determine the constraints imposed by baryon acoustic oscillations on void models.

Main Methods:

Fitting a void profile to cosmic microwave background (CMB) data.

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Last Updated: Jun 26, 2026

Scattering And Absorption of Light in Planetary Regoliths

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Published on: July 1, 2019

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Published on: November 15, 2013

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Analyzing supernova observational data.

Calculating constraints from the radial baryon acoustic scale.

Main Results:

An appropriate void profile can be adjusted to fit CMB and supernova data.
Achieving this fit necessitates either a fine-tuned primordial spectrum or a significantly reduced Hubble rate.
Radial baryon acoustic scale measurements provide stringent constraints on void models.

Conclusions:

Void models face significant challenges in explaining cosmic acceleration.
The requirement for fine-tuning or an unphysically low Hubble rate raises concerns about their validity.
Observational constraints, particularly from baryon acoustic oscillations, strongly challenge the viability of void models for cosmic acceleration.