# Theoretical Particle Physics

Understanding the fundamental nature of forces, particles, and space-time geometry. The origin of mass, grand unification of the forces, general relativity, quantum field theory and string theory and their applications, early universe cosmology including inflation and eternal inflation, holography, quantum gravity.

Research in the Stanford Institute for Theoretical Physics (SITP) includes a strong focus on fundamental questions about the new physics underlying the Standard Models of particle physics and cosmology, and on the nature and applications of our basic frameworks (quantum field theory and string theory) for attacking these questions. Central areas of research include: what governs particle theory beyond the scale of electroweak symmetry breaking? How do string theory and holography resolve the basic puzzles of general relativity, including the deep issues arising in black hole physics and the study of cosmological horizons? Which class of models of inflationary cosmology captures the physics of the early universe, and what preceded inflation? Can we develop new techniques in quantum field theory and string theory to shed light on mysterious phases arising in many contexts in condensed matter physics (notably, in the high temperature superconductors)? There is considerable cross-fertilization in some of these endeavors with faculty in the SLAC Theory Group, the Kavli Institute for Particle Astrophysics and Cosmology, and the Theoretical Condensed Matter portion of SITP.