Cosmology and Relativity

Our group forms the Tufts Institute of Cosmology. Members are engaged in fundamental research in theoretical physics and cosmology, with connections to gravitation, elementary particle physics, and quantum field theory.

Some of the central research directions include:

1. Early Universe Physics, including inflation, quantum cosmology, and the multiverse,
2. Topological Defects, including cosmic strings and domain walls,
3. Fundamental Aspects of Gravitation, including quantum fluctuations, energy conditions, and constraints on theories of gravitation,
4. Particle Cosmology, including dark matter and models of particle production.

Research in these areas involve faculty, postdocs, long term visitors, graduate and undergraduate students. The group has regular seminars including a joint seminar series with MIT.

Research Faculty

• Professor Hertzberg's work involves the study of dark matter, models of inflation, reheating, constraints on theories of gravitation, and quantum entanglement.
• Professor Olum's work involves the observation of gravitational waves using pulsar timing, as part of the NANOGrav collaboration, and the study of cosmic strings, including advanced numerical simulations.
• Professor Kumar works at the intersection of theoretical particle physics and early Universe cosmology. The primary questions that drive his research are the microphysics of cosmic inflation and the nature of dark matter, as well as any associated dark sector. Some of the specific topics he has recently worked on include novel observational signatures of cosmic inflation, primordial non-Gaussianity and its connection to particle theory, axion cosmology, and gravitational waves.
• Emeritus Professor Ford's work involves the study of quantum fields in curved spacetime, including negative energy densities and quantum fluctuations of the vacuum.
• Emeritus Professor Vilenkin's work involves the study of eternal inflation, probabilities in the multiverse, quantum cosmology, and cosmic strings.