2022/02/18(Fri)
11:00 -12:00
五樓第一會議室 5F, 1st Meeting Room
視訊演講 Video Seminar [ Meeting Link / ID: 2516 639 4427 / Password: BGfeBtc4F78 ]
Title
The cosmological constant problem, Fab Four, and well-tempered cosmology
Speaker
Dr. Reginald Christian Bernardo (Institute of Physics, Academia Sinica)Abstract
The cosmological constant problem remains to be physics' biggest tension between theory and observation. Conceding to this means accepting an uncomfortable fine-tuning of at least fifty orders of magnitude. Instead, we briefly review Steven Weinberg's no-go theorem and how this paved the direction to self-tuning fields. We then recognize two ways of realizing a self-tuning mechanism in scalar-tensor theories: through Fab Four models and well-tempered cosmology. We discuss the core property "degeneracy" shared by such models which works to admit a low energy vacuum state independent of an arbitrarily large cosmological constant. We end with the recent progress in both Fab Four and well-tempered models, and draw future directions.
Language
演講語言 (Language): in English