Cosmology is the study of the universe, its origin, evolution, and fate. It is an area that combines all aspects of physics, since gravity, electromagnetism, elementary particles, nuclear physics, etc. are all important. Today, there is an overwhelming evidence that our universe began in a Hot Big Bang amost fourteen billion years ago, with the Solar System (including Earth) forming about five billion years ago. Quasars and early galaxies have been observed which formed when the universe was less than a billion years old. We can see them now because the light travel time to them is so large. Even earlier times are studied through the observation of the Cosmic Microwave Background, emitted a few hundred thousand years after the Big Bang, when the universe was very smooth. Remarkably, this background was predicted in 1946 by the George Gamow and a bit later by young researchers Ralph Alpher and Robert Hermann but not detected until the 1960's when their work had been nearly forgotten. At stages earlier than the microwave background we can calculate the behavior of the universe using known physics and Big Bang Nucleosynthesis back to about 0.001 second. Today's universe is very lumpy, and one of the challenges we face now is to understand how it became that way from such a smooth beginning. An even greater challenge is to understand whether and why the expansion of the Universe seems to be accelerating.
The Cosmology Group at the University of Kansas specializes in studying the evolution of structure. It is known that if there are small irregularities in the otherwise smooth mass distribution, they will grow in the expanding universe due to the action of gravity. Ripples of just the right size were found in the microwave background by NASA's COBE and WMAP satellites. Exploration of the evolution of of the Universe continues with observations at a variety of wavelenghts. We do analysis and computer simulations of the evolution of structure. We also do statistical studies to compare the distribution of matter in the universe to that which appears in both observations and simulations. This kind of comparison helps us understand events in the very early universe, as well as shed light on the nature of the unknown dark matter. The group has been part of an international team using the Hubble Space Telescope to observe quasars in an attempt to learn the distribution of matter by its effect on their spectra. This can probe how the distribution evolved over the time back to the quasar's emission.
Opportunities exist for students to be involved in research at both the graduate and undergraduate level. Undergraduates work with us primarily on computer simulations and analysis with possible funding from the Research Experiences for Undergraduates program of the National Science Foundation. Nearly every year publications appear with undergraduate coauthors. Our undergraduate resarcher pool produced four Goldwater Scholars and one NSF Graduate Fellow. Research leading to a physics Ph.D. (or possibly an M.S. in Computational Physics and Astronomy) is also possible. Graduate students are working in data analysis, study of simulations, as well as performance of simulations on high-performance computers. We maintain an active international net of collaborators including sites in Germany, India, England, Denmark, France (IAP and OCA) and Poland. Opportunities exist for exchange programs for interested students.
Recent research publications can be found here.
Last Updated: February 22, 2007