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While I am primarily a builder of mm and sub-mm wave instruments, my science interests center around the study of Cosmology and (more recently) the evolution of galaxies and large scale structure. The mm and sub-mm wavelength bands provide the most direct and exciting paths to learning more about these fields.

More than 99% of the photons in the universe can be accounted for by three sources of radiation that lie within the millimeter and sub-millimeter wavelength bands. The dominant astrophysical source of photons is the Cosmic Microwave Background (CMB) radiation, whose properties contain a wealth of information about the early universe, long before any stars or galaxies formed. Recently, two instruments on the COBE satellite detected a second form of ``cosmic radiation'', the Cosmic Infrared Background (CIB) radiation which is presumed to be the remnant emission from a dusty population of early galaxies. Finally, there is a relatively large mm-wave flux from thermal emission from warm (~10-100 K) dust in our own Milky Way galaxy and from nearby dusty galaxies.

Distant galaxies are the repository of most of the luminous matter in the Universe, and as such, they hold the keys to many fundamental questions about its history, fate, and composition. The study of galaxy evolution has advanced significantly during the last 15 years with the Hubble Space Telescope and large optical and infrared facilities. More recently, sensitive observations at millimeter and submillimeter wavelengths have revealed a population of optically obscured galaxies at high redshift (Smail et al. 1997, Barger et al. 1998, Hughes et al. 1998, Eales et al. 1999). This new population, now known as the submillimeter galaxy population (SMGs), has a number density which clearly indicates 10-50 times more members than what is expected from a population of galaxies whose luminosity does not evolve with time (Guiderdoni et al. 1998, Blain et al. 1999).

To make the SMG population even more interesting from a galaxy evolution point of view, multi-wavelength follow-up studies of a small number of sources suggest that these are massive young galaxies seen during their formation and rapid-growth epochs, with an inferred star formation rate exceeding 1000 $M_\odot$/yr, or about 1000 times that of the Milky Way galaxy (Blain et al. 2002). Unfortunately, the combination of their faintness at nearly all wavelengths (particularly in the optical) and low signal/noise of the existing mm/submm data has greatly hampered both the identification of sources and follow-up investigations. Dramatic new progress on mapping large areas of sky at 850~$\mu$m will ultimately be made by the new SCUBA-2 instrument on the 15~m JCMT -- pinning down the characteristics of the bright-end of the source spectrum. With 10 times more sensitivity than SCUBA-2 we will attack the faint end of the source spectrum in oder to finally understand the connection between SMGs and their more local analogs (Lyman-break galaxies, massive ellipticals, and ULIRGS) and ultimately construct a complete observational framework for the cosmic evolution of galaxies and their star formation history.