Applying the lessons learned in quantum information theory to gain a better understanding of quantum mechanics itself. Is quantum theory simply a new type of probability theory? Exploring new directions towards combining quantum theory with gravity.
Physics beyond the standard model: theories of elementary particles with extra space dimensions (large, small, warped and flat); supersymmetry; grand unification; dark matter; inflation and dark energy; as well as relationships between the different subjects.
Observational cosmology, with particular focus on the formation and evolution of large scale structures in our universe like clusters of galaxies as large as 500 million light years. “Weighing” the universe, and mapping out the mysterious dark matter it contains.
Cosmology as a natural meeting ground for fundamental theory (e.g. superstring theory or quantum gravity) and observations. Exploring how seeds laid down in the very early universe developed into the large scale structure we observe in the universe today.
Implications of high-energy elementary particle physics for physics of the early universe and its evolution (Big Bang, creation of matter, formation of galaxies, etc). And vice-versa: implications of observable cosmological data for fundamental physics.
Particle physics, cosmology, and the study of a wide variety of theoretical models – most notably ones involving extra dimensions of space. Randall works on several of the competing models of string theory in the quest to explain the fabric of the universe.
Philosophy of physics, puzzles about the content and status of foundational principles – the logic of physicists’ basic assumptions, especially with regards to space and time, and the history of science, e.g. exactly how Einstein made his discoveries.
Removing the mystery from quantum mechanics, the Bohmian perspective – a way of describing the motion of quantum particles, and applying this to spacetime singularities (where gravity becomes infinite) like those inside a black hole.
Quantum gravity, quantum processes in the early universe, evaporation of black holes, limits on the measurements made by real detectors (coupled to the environment), and with regards to mathematical problems, studying techniques rather than finding solutions.