Open and Unoriented Strings from Topological Membrane - I. Prolegomena

We study open and unoriented strings in a Topological Membrane (TM) theory through orbifolds of the bulk 3D space. This is achieved by gauging discrete symmetries of the theory. Open and unoriented strings can be obtained from all possible realizations of $C$, $P$ and $T$ symmetries. The important role of $C$ symmetry to distinguish between Dirichlet and Neumman boundary conditions is discussed in detail.Comment: 2+43 pages, 25 figures. Major changes, mostly in subsection 4.5 and References adde

One-loop stau masses in the effective potential approach

We calculate the one-loop contributions to the tau slepton masses in the Minimal Supersymmetric Standard Model in the effective potential approach. For the majority of parameter space under study, those corrections are shown to elevate the value of the lightest stau mass.Comment: 11 pages, 3 figure