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\begin{document}

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\section*{Schweigert}

\hypertarget{boundary_conditions_and_defects_in_threedimensional_topological_field_theory}{}\subsection*{{Boundary conditions and defects in three-dimensional topological field theory}}\label{boundary_conditions_and_defects_in_threedimensional_topological_field_theory}

Abstract: Codimension-one defects in quantum field theories have proven to be natural objects that carry much interesting structure. In the talk, we concentrate on topological quantum field theories in three dimensions, with a special focus on Dijkgraaf-Witten theories with abelian gauge group. We explain that symmetries in these topological field theories are naturally defined in terms of invertible topological surface defects and are thus Brauer-Picard groups.



\end{document}