# Metastring theory

- Institution: CERN
- Department: TH Theoretical Seminar
- Speaker: Robert Prof. Leigh
- Year: 2015
- Language: English
- Source: [CERN](https://videos.cern.ch/record/3006239)
- Licence: [CERN](http://copyright.web.cern.ch)
- Who can watch: Teens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

T-duality has long tantalized us in giving a window into stringy geometry. In recent years, we have developed metastring theory, a string theory in which the target space is not interpreted a priori as space-time but rather as a sort of phase space. By generalizing in this way, we obtain a theory in which space-time, and space-time locality, can be regarded as emergent. T-duality is then realized as a sort of Fourier transform, selecting a space-time based on how the theory is probed. We find that metastring theory is essentially unique; there is a purely quantum notion of space-time that we call modular space-time, and all of the usual string compactifications arise from it by various `classical' limits..

0:00:00 Slide 1

0:00:57 Slide 2

0:02:36 Slide 3

0:03:55 Slide 4

0:06:09 Slide 5

0:07:25 Slide 6

0:07:39 Slide 7

0:07:56 Slide 8

0:09:14 Slide 9

0:10:40 Slide 10

0:11:19 Slide 11

0:13:56 Slide 12

0:15:33 Slide 13

0:17:17 Slide 14

0:19:37 Slide 15

0:21:21 Slide 16

0:23:53 Slide 17

0:26:21 Slide 18

0:28:06 Slide 19

0:30:20 Slide 20

0:32:09 Slide 21

0:32:15 Slide 22

0:34:51 Slide 23

0:36:12 Slide 24

0:39:41 Slide 25

0:41:42 Slide 26

0:43:36 Slide 27

0:46:11 Slide 28

0:47:45 Slide 29

0:47:59 Slide 30

0:50:43 Slide 31

0:52:58 Slide 32

0:53:13 Slide 33

0:53:40 Slide 34

0:53:44 Slide 35

0:53:48 Slide 36

0:54:20 Slide 37

0:54:24 Slide 38

0:55:06 Slide 39

0:55:55 Slide 40

0:56:27 Slide 41

0:59:47 Slide 42

1:03:34 Slide 43

1:03:54 Slide 44

1:03:58 Slide 45

1:04:02 Slide 46

## Lectures

1. [Metastring theory](https://invisiblenetwork.ai/learn/cern/3006239/f16954258611), 1 h 10 min (CERN's player)