| Speaker: | Kazuya Koyama (Portsmouth U.) |
|---|---|
| Title: | Cosmological tests of gravity |
| Date (JST): | Tue, Jul 22, 2025, 15:30 - 17:00 |
| Place: | Seminar Room A |
| Abstract: | The discovery of the accelerated expansion of the Universe has come relatively late in our study of the cosmos, but in showing that gravity can act repulsively, it has opened up many new questions about the nature of gravity and what the Universe might contain. Is the acceleration being driven by dark energy?  Or is general relativity itself in error, requiring a modification at large scales to account for the late acceleration? Structure formation in our Universe can be different even if the geometry of the homogeneous and isotropic universe is the same in these two classes of models, offering a possibility to distinguish between them observationally. I will discuss cosmological tests of dark energy and modified gravity models using the latest cosmological observations such as the recent results from DESI and conclude with prospects for upcoming results from Euclid. |
