An Introduction to Double String Theory and Non-Riemannian Backgrounds

Abstract: This talk introduces Double Field Theory (DFT) in the context of string theory and its application to "non-Riemannian" backgrounds following arXiv:2008.03084. We will study a unique case where the BRST cohomology simplifies to only include states from the first excited level. To keep the discussion pedagogical, I will briefly review BRST quantisation and demonstrate the modular invariance of the 1-loop torus partition function as a consistency check. No prior DFT expertise is required, all are welcome.

condensed mattergeneral relativity and quantum cosmologyHEP - theorymathematical physicsdifferential geometry

Audience: advanced learners

( paper )

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Europe and Pacific Theoretical Physics

Series comments: European and Pacific Theoretical Physics is a group that runs online seminars and talks across broad topics in mathematical and theoretical physics. Our goal is to share concepts across continents to bring about a deeper understanding of cutting-edge topics in physics.

The talks are informal, and anyone can participate, so please reach out if you would like to present one week!

Extended notes & presentation material are uploaded to "Past talks". Please click on the title of a talk, and then click on "paper" or "slides" to see more. Our focus for 2025 was on Generalised (Categorical) Symmetries, following the lecture notes found here: arxiv.org/pdf/2411.09082.

The reading course seminars are scheduled to resume in 2026. If you would like to present material, please reach out.

Zoom link: unibe-ch.zoom.us/j/6801537904

Talks may be uploaded to YouTube: www.youtube.com/@eupactp

Mailing list sign-up: forms.gle/StswcjC7RbXWuvAr8

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