Abstract This review provides an introduction to non-geometric backgrounds in string theory. Starting from a discussion of T-duality, geometric and non-geometric torus-fibrations are reviewed, generalised geometry and its relation to non-geometric backgrounds are explained and compactifications of string theory with geometric and non-geometric fluxes are discussed. Furthermore covered are doubled geometry as well as non-commutative and non-associative structures in the context of non-geometric backgrounds.

中文翻译：

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弦论中的非几何背景

摘要 本综述介绍了弦论中的非几何背景。从 T 对偶性的讨论开始，回顾了几何和非几何环面纤维化，解释了广义几何及其与非几何背景的关系，并讨论了具有几何和非几何通量的弦理论的紧凑化。此外还涵盖了双几何以及非几何背景下的非交换和非关联结构。