About
String theory suggests a unique and unambiguous augmentation of General Relativity, in which the entire closed-string massless NS-NS sector is promoted to stringy graviton fields. O(D,D) T-duality then uniquely fixes the coupling of this 'Stringy Gravity' to other matter, leading to a generalization of Einstein's equations with an enhanced energy-momentum tensor. In this talk I will explore the resulting cosmological implications and show that this yields an enriched framework beyond typical string cosmology, with solutions characterized by two equation-of-state parameters (w,\lambda) rather than one (w). This includes a line in parameter space where GR-like solutions with constant dilaton are admitted for any w. However, while apparently present on the GR line, there is no de Sitter solution arising from an O(D,D)-symmetric cosmological constant or scalar field with positive energy density, suggesting that de Sitter may simply be an artefact of GR and belong to the swampland..
0:00:00 Slide 1
0:00:40 Slide 2
0:01:26 Slide 3
0:02:19 Slide 4
0:02:35 Slide 5
0:04:38 Slide 6
0:06:03 Slide 7
0:07:14 Slide 8
0:08:33 Slide 9
0:09:14 Slide 10
0:10:37 Slide 11
The talk
Credits and licence
- Institution
- CERN
- Department
- Conferences & Workshops
- Speaker
- Stephen Angus
- Year
- 2019
- Language
- English
- Source
- CERN
- Licence
- CERN, as CERN states it. CERN's terms
- Attribution
- © CERN. CERN provides its audiovisual media free of charge for educational and informational use, credited to CERN; this lecture is shown in CERN's own player.
- Who can watch
- CERN gives no rating. Invisible Network shows it to Teens profiles and older, judged from what the source says about it. How courses are placed