Starbursts: Lessons for the Origin and Evolution of Galaxies and the Inter-Galactic Medium

Abstract

Starbursts are episodes of intense star-formation that occur in the central regions of galaxies, and dominate the integrated emission from the galaxy. They are a significant component of the present- day universe, being the site of $\sim$ 25% of the high-mass star- formation. They offer unique `laboratories' for testing our ideas about star-formation, the evolution of high-mass stars, and the physics of the interstellar medium. They serve as local analogs of the processes that were important in the origin and early evolution of galaxies and in the heating and chemical enrichment of the inter-galactic medium. In this contribution I review starbursts from this broad cosmogonical perspective, stressing several key lessons we have learned from starbursts: 1) Violent, transient events play a significant role in the origin and evolution of galaxies. 2) Galaxies do not evolve as `Island Universes': starbursts are triggered by galaxy interactions and produce outflows of hot chemically-enriched gas that `pollute' the inter- galactic medium. 3) Dust dramatically affects of view of high-mass star-formation in starbursts and (probably) in high-redshift galaxies. Throughout this review I emphasize the importance of space-based observations in understanding starbursts.