The field of Cosmic Microwave Background (CMB) observations has given us some of the most exciting discoveries in cosmology in the past decade. The Lee et al. letter represents the MAXIMA experiment's evidence for a third acoustic peak in the CMB power spectrum. The existence of peaks beyond the first peak greatly bolsters the argument that inflation occurred in the early universe. At roughly the same time, the DASI (Degree Angular Scale Interferometer) and BOOMERanG (Balloon Observations of Millimetric Extragalactic Radiation and Geophysics) experiments presented their results on higher order peaks. Together, the three experiments firmly established the shape of the CMB power spectrum. The Lee et al. paper is highly cited since it represents an important part of this exciting set of discoveries.

  Could you summarize the significance of your paper in layman's terms?

The best current model of the universe starts with the Big Bang. After the Big Bang, the universe was remarkably uniform with variations in density that could be measured in the parts per million. These slight variations however, are very important. As the universe expanded these small variations grew with time and eventually led to stars, galaxies, the earth and us. We can take baby pictures of the universe 300,000 years after the Big Bang by observing hot and cold spots in the sky from the Cosmic Microwave Background (CMB), the leftover radiation from the Big Bang. The MAXIMA experiment, along with BOOMERanG and DASI, was able to image these faint hot and cold spots on the sky. MAXIMA (Millimeter Anisotropy eXperiment IMaging Array) was able to take a picture with 10 arc-minute resolution (the Earth’s moon is 30 arc minutes), which was unprecedented. Using this high resolution, we were able to see characteristic spots at several different sizes. These spots tell us that the overall topology of the universe appears to be flat—that is, light travels in straight lines. Knowing that the universe is flat helps us understand the ultimate fate of the universe. Right now, it appears the universe will expand forever.

  How did you become involved in this research?

I became interested in the CMB while I was a graduate student working on an experiment to look for WIMP (Weakly Interacting Massive Particles) dark matter. Luckily, I was able to work on the MAXIMA experiment as a postdoctoral fellow.