Testing galaxy formation and dark matter with low surface brightness galaxies.

Area of Science:

• Cosmology
• Astrophysics
• Galaxy Formation

Background:

• Galaxies are fundamental cosmic structures; galaxy formation theory aims to elucidate their origins.
• Early theories heavily relied on non-baryonic cold dark matter.
• Observational data, particularly from low surface brightness galaxies, revealed discrepancies with initial dark matter models.

Purpose of the Study:

• To trace foundational ideas in galaxy formation theory.
• To highlight the challenges posed by observational data to cold dark matter models.
• To explore the predictive successes of Modified Newtonian Dynamics (MOND) as an alternative.

Main Methods:

• Review of foundational concepts in galaxy formation theory.
• Analysis of observational constraints from low surface brightness galaxies.
• Comparative assessment of dark matter models versus MOND's predictive power.

Main Results:

• Initial galaxy formation models based on cold dark matter faced significant observational challenges.
• Auxiliary hypotheses like feedback were introduced to reconcile dark matter models with data.
• Modified Newtonian Dynamics (MOND) demonstrated unexpected predictive accuracy, challenging the prevailing dark matter paradigm.

Conclusions:

• The success of MOND in specific predictions raises fundamental questions about the nature of gravity and dark matter.
• There is a need to reconcile the flexibility of dark matter models with the predictive power of MOND.
• Further investigation is required to understand why MOND aligns with observations if the universe is indeed composed of cold dark matter.