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Updated: Jul 17, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Can cosmic structure form without dark matter?
Scott Dodelson1, Michele Liguori
1Particle Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, Illinois 60510-0500, USA.
Physical Review Letters
|February 7, 2007
Summary
Dark matter evidence, like large cosmic overdensities, requires enhanced structure growth since recombination. This study shows Bekenstein
Area of Science:
- Cosmology
- Astrophysics
- Theoretical Physics
Background:
- The existence of dark matter is supported by observations of large overdense regions in the Universe.
- These overdense regions imply that cosmic perturbations have grown significantly since the epoch of recombination (z*).
- Standard cosmological models based on general relativity do not fully explain this enhanced growth without dark matter.
Purpose of the Study:
- To investigate alternative theories that can explain the observed enhanced growth of cosmic structures.
- To explore whether modified gravity theories can account for the observed overdensities without invoking dark matter.
Main Methods:
- Theoretical analysis of structure formation within alternative gravity frameworks.
- Focus on Bekenstein's relativistic version of modified Newtonian dynamics (MOND).
Main Results:
- Enhanced growth of perturbations, a key indicator for dark matter, can occur in alternative gravity theories.
- Specifically, Bekenstein's relativistic MOND model demonstrates the potential for such enhanced growth.
Conclusions:
- The observed large-scale structures in the Universe may be explained by modified gravity theories.
- Bekenstein's relativistic MOND offers a viable alternative to dark matter for explaining cosmic structure formation.
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