Anthony N Aguirre
|Affiliations||Astronomy & Astrophysics Department|
|Web Site||Web Page|
|Campus Mail Stop||Physics Department|
|1156 High Street|
Santa Cruz, CA
Research InterestsMy current research falls in three main categories. The first and probably largest is the study of cosmological inflation and eternal inflation. Inflation is a compelling component of the standard model of cosmology with considerable observational success. Eternal inflation, which is generic in inflation models, describes a situation where inflation goes on forever, ending only locally and thus continually creating “pockets” or “bubbles” of non-inflation that might have diverse properties and one of which might contain our observable universe. (See here for a review article of mine.) My current research, which assesses whether collisions between expanding “bubble universes” could leave an observable imprint on the cosmic microwave background or other cosmological observables.
A second set of research focuses on: heavy-element enrichment of the intergalactic medium. Heavy elements, such assilicon, oxygen, and carbon (or “metals” is astro-parlance), are formed inside stars, which are located in galaxies. Yet, these elements are also observed in the "intergalactic medium" between galaxies. These metals may ultimately provide a "fossil record" for star and galaxy formation during the very early universe. I have tackled these issues using theory (such as computer simulations to test various ejection scenarios) and observation (analyzing quasar spectra to see how the elements are distributed outside of galaxies). A major current project seeks to compare a new set of top-notch cosmological simulations to the observations of metal enrichment, to test and constrain these simulations and the physics of metal-ejection that they implement. A second project will use the observed abundances in conjunction with modeling of the intergalactic medium, to test and constrain models of the “ultraviolet background” at high-redshift, which is a combination of radiation from all stars and quasars, and provides a constraint on the history of star and galaxy formation, as well as a crucial input into efforts to model physical cosmology and galaxy formation.
The third category is "other": I’ve also worked on a number of Past projects/topics, including
Dark matter and population III stars
Radically different cosmologies which don’t turn out to be true, but might still be interesting
Black holes (possibly exploding ones)
How to make a universe in your basement (or not)
Can modified gravity substitute for dark matter?