General In general, my research interest is the phenomenology of elementary particles. [see also here ] That is to say, I investigate the properties of elementary particles which may be tested experimentally (usually at particle accelerators) and the possible implications of various models which have been proposed to explain the these building blocks which make up the world around us. Below are some specific topics of my ongoing research. CP Violation in B Physics If CP were a symmetry of nature, all physical experiments would be the same if you replaced each particle of matter with anti-matter (i.e. C=charge conjugation) and reflected the setup in a mirror (i.e. P=parity). In fact most of the processes known do respect this symmetry so processes that violate CP are trying to tell us something deep about nature. In the 1960's it was discovered that the long lived K0 meson decays to positrons slightly more than electrons therefore violating CP. This meson also violates CP quantum mechanically by decaying to two pions. Since that time, no other systems that violate CP have been discovered until early 2001 when strong evidence has emerged from the SLAC and KEK B-factories that CP is violated in the decay B0 -> psi+K. In fact this result is not totally unexpected since the Standard Model of Particle Physics explains CP violation in the K0 meson and predicts that it should also be present in the B0 meson. In fact, the study of CP violation in the B meson offers the chance to probe the parameters of the standard model in detail or find discrepancies that indicate new physics. In this area of research, I have investigated a number of processes which could shed light on these parameters. CP Violation in Top Physics In fact, there is another example of CP violation in nature that is completely unexplained: the fact that matter predominates over anti-mater in the universe. If the CP violation which has been studied in the laboratory in the K and B mesons originates from the Standard Model (as is expected), there is still a mystery since this model does not contain enough CP violation to produce the observed excess of matter. To do the job, there must be some deeper source of CP violation and indeed many models for New Physics fit the bill; Super Symmetry, Extended Higgs sectors. In many of these cases, evidence should be present in production and decays of the top quark. These quarks are already produced at the Tevatron at Fermilab and in the future will be produced in large numbers at the LHC at CERN as well as at proposed high energy electron-positron colliders In this area I have studied the signatures of CP violation which could be observed at these colliders. Phenomenology of Large Extra Dimensions The excess of matter over anti-matter in the Universe certainly suggests that there must be some physics beyond the Standard Model but in addition there is an inherent difficulty of the Standard Model, the hierarchy problem which leads to a situation where the parameters of the Standard Model are unstable unless new physics is present by energy scales of order 1TeV. Theorists have long speculated strings or their generalization, superstrings, provide an appealing model for the ultimate nature of matter. In such theories the fundamental entities are one dimensional strings rather than point-like particles considered in standard quantum field theory. The only problem is that such theories often require many extra spatial dimensions for consistency. It has long been understood that one can allow for extra dimensions that beyond the 3 space and 1 time of ordinary experience by having the additional dimensions be short in length and thus unobservable by current experiments. In the past few years, however, it has been realized that some of the extra dimensions could be large enough to be seen experimentally. This results from the fact that at short distances the force of gravity will be stronger than suggested by Newton's law. At high enough momentum (corresponding to short distances by Heisenberg's Relation), the scattering of particles may well by dominated by gravitational effects. In this area, I have studied how the onset of such interactions may be observed at the Tevatron, LHC or electron-positron colliders.