Works on particle theory and cosmology, focusing on physics beyond the Standard Model (SM). Topics include dark matter and dark energy, early universe dynamics, collider phenomenology, Higgs physics, and model building. Geller's research is focused on tackling major theoretical problems in our understanding of the universe and finding new exciting experimental and observational predictions that can help us exclude or discover new phenomena.
Research achievements include: significant work on the neutral naturalness paradigm of addressing the Higgs hierarchy problem, with emphasis on the twin Higgs model. In addition, Geller and collaborators have proposed the possibility of learning about the early universe dynamics using the angular information in a possible gravitational wave background. Geller has also proposed a new idea of solving the hierarchy problem of the Higgs with new dynamics at cosmic inflation.
Future directions include: searching for cosmological solutions to the cosmological constant and the Higgs hierarchy problem, studying new ideas in the detection and production of dark matter bound states, looking for new phenomena that can give rise to striking signals in the future observations of cosmic microwave background, large scale structure, and gravitational waves.