Published in Physics Reports, Volume 495, Issue 2-3, p. 33-86., 2010.
astro-ph/1006.5394

For a PDF version of the article, click here.

GALAXY FORMATION THEORY

Andrew J. Benson


California Institute of Technology, MC350-17, 1200 E. California Blvd., Pasadena, CA 91125, U.S.A.


Abstract: We review the current theory of how galaxies form within the cosmological framework provided by the cold dark matter paradigm for structure formation. Beginning with the pre-galactic evolution of baryonic material we describe the analytical and numerical understanding of how baryons condense into galaxies, what determines the structure of those galaxies and how internal and external processes (including star formation, merging, active galactic nuclei, etc.) determine their gross properties and evolution. Throughout, we highlight successes and failures of current galaxy formation theory. We include a review of computational implementations of galaxy formation theory and assess their ability to provide reliable modeling of this complex phenomenon. We finish with a discussion of several "hot topics" in contemporary galaxy formation theory and assess future directions for this field.


Keywords:galaxies, cosmology, galactic structure, galaxy evolution, galaxy formation


Table of Contents

INTRODUCTION

BACKGROUND MATERIAL
Background Cosmology
Structure Formation
Halo Formation
Halo Mass Distribution
Halo Formation Distribution
Halo Structure

PRE-GALACTIC EVOLUTION OF BARYONS
Cold or Hot Accretion (Shocks)
Cooling
Atomic
Compton Cooling
Molecular Hydrogen Cooling
Heating
Photoheating
Heating from Feedback
Preheating
Thermal Conduction
Fate of Cooling Gas

GALAXY INTERACTIONS
Galaxy Orbits
Gravitational Interactions
Mergers
Tidal Destruction
Harassment
Hydrodynamical Interactions
Ram pressure

GALACTIC STRUCTURE
Disk Formation
Sizes
Stability
Bars/Spiral Arms
Spheroid Formation
Major Mergers
Secular Evolution
Sizes

STAR FORMATION, AGN AND FEEDBACK
Star Formation
Black Hole Formation
Feedback
Supernovae/Stellar Winds
AGN
Chemical Enrichment
Stellar Populations
Steller Population Synthesis
Dust Absorption and Re-emission
Absorption by the Intergalactic Medium

COMPUTATIONAL TECHNIQUES
N-body/Hydro
Semi-Analytic
Halo Occupation Distributions

TOPICS OF CURRENT INTEREST
The First Galaxies
The Formation and Sizes of Galaxy Disks
The Overcooling Problem
Local Group Dwarf Satellites
The Origins of the Hubble Sequence

FUTURE DIRECTIONS

SUMMARY

REFERENCES

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