Testing Galaxy Formation and Dark Matter with Low Surface Brightness Galaxies

TL;DR

This paper reviews galaxy formation theories, emphasizing the challenges faced by dark matter models in explaining low surface brightness galaxies and highlighting the predictive successes of MOND as an alternative.

Contribution

It critically examines the limitations of dark matter models and underscores the predictive power of MOND in galaxy formation, especially for low surface brightness galaxies.

Findings

Dark matter models struggle with low surface brightness galaxy observations.

MOND accurately predicts certain galaxy dynamics without dark matter.

Feedback mechanisms are invoked to reconcile models with observations.

Abstract

Galaxies are the basic structural element of the universe; galaxy formation theory seeks to explain how these structures came to be. I trace some of the foundational ideas in galaxy formation, with emphasis on the need for non-baryonic cold dark matter. Many elements of early theory did not survive contact with observations of low surface brightness galaxies, leading to the need for auxiliary hypotheses like feedback. The failure points often trace to the surprising predictive successes of an alternative to dark matter, the Modified Newtonian Dynamics (MOND). While dark matter models are flexible in accommodating observations, they do not provide the predictive capacity of MOND. If the universe is made of cold dark matter, why does MOND get any predictions right?