The Galactic Center is being actively explored at radio, sub-millimeter, infrared, X-ray and gamma-ray wavelengths, with unprecedented clarity and spectral resolution. This research will study in detail the strong field effects associated with the central black hole, with the expectation that they will produce observationally testable signatures. Diverse lines of evidence, such as the 80 minute period at wavelength 1.3 millimeters, the 17 minute modulation of infrared emission, and the 10 minute variability during X-ray flares, argue for a new intense theoretical investigation into the structure of spacetime close to the black hole. Using semi-analytical analysis, numerical methods, and ray-tracing calculations, this project will consider these variabilities, as well as the tentative 106 day periodicity at centimeter wavelengths, and develop a theoretical framework for the eventual imaging of the black hole accretion system's shadow using millimeter and sub-millimeter global-baseline interferometry.
This investigator has many years of experience training young scientists, many of whom have gone on to become scientific leaders in their own right. He is also very effective at bringing science to a wider audience, via books, tours, and many public presentations.
