Research in theoretical physics will include studies of transport processes in matter at high densities and temperatures that pertain to particle physics, nuclear physics, plasma physics, astrophysics and condensed matter physics. A study of elementary processes associated with the thermal evolution of neutron stars together with interpreting the recent observational data will be performed. This study is important because neutron star matter is unique (the densest stable matter in the universe) in providing us with information that is not easily accessible in laboratory experiments. In addition, the properties of a soon-to-be-created new plasma---the non- relativistic electron-positron plasma---will be studied. The importance of this study lies in deepening our understanding of the plasma through comparison with conventional plasma systems and, more importantly, helping guide the experimental efforts in creating the electron- positron plasma in the laboratory.