Abstract by Nicholas Van Alfen
Nicholas Van Alfen
Physics and Astronomy
J. Ward Moody
Measuring the Temperature Evolution of Galaxy Gas Clouds with Distance
Because light takes time to travel to us, when we look at distant galaxies, we are seeing how they appeared millions or billions of years ago. So deep surveys are surveys back in time as well. According to big bang cosmology, the universe evolves with time, which means we should see evolution as a function of distance. One such evolution is the temperature of galaxy gas clouds. They should be hotter in the past than they are now since earlier in the universe there were more young, hot stars embedded within them than there is today. We are looking for this evolution back to 40% of the distance to the big bang using 27,000 spectra from the Sloan Digital Sky Survey. We report on the method we are using and the progress of this study.