My  interests center mainly on the interface between cosmology and particle physics.  I have very strong interests in the quantum mechanics/field theory involved in inflationary cosmologies.  This has led me to spending a great deal of time developing a formalism that can be used to describe quantum fields in non-equilibrium environments, such as occur during and immediately after an inflationary phase.  This formalism has also had very interesting applications to the so-called Dark Energy problem.

I am currently involved in trying to understand how current and future measurements of the Cosmic Microwave Background Radiation could detect effects coming from Planck-Scale physics, as well as constructing models that describe the so-called Dark Energy component of the Universe.

Selected Publications

R. Holman and A. J. Tolley, "Enhanced Non-Gaussinity from Excited Initial States," submitted to JHEP (2007).

H. Collins and R. Holman, "Trans-Planckian Signals from the Breaking of Local Lorentz Invariance," submitted to PRD (2007).

R. Holman and L. Mersini-Houghton, "Why the Universe Started from a Low Entropy State," Phys. Rev D74 123510 (2006).

R. Holman and J. Hutasoit, "Systematics of Moduli Stabilization, Inflationary Dynamics and Power Spectrum," JHEP 0608 053 (2006).

H. Collins and R. Holman, "The Renormalization of the Energy-Momentum Tensor for an Effective Initial State," Phys. Rev. D74 045009 (2006).

R. Holman and L. Mersini-Houghton, "A Fly in the SOUP," Phys. Rev. D74 043511 (2006).

R. Holman and M. R. Martin, "Boundary Localized Symmetry Breaking and Topological Defects," Phys. Rev. D73 085006 (2006).