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arXiv 2009.034002020-09hep-thgr-qcmath-phmath.MP

Quantum (Matrix) Geometry and Quasi-Coherent States

Harold C. Steinacker

备注：: 35 pages. V2: minor corrections. V3: minor improvements
DOI：: 10.1088/1751-8121/abd735

英文摘要：

A general framework is described which associates geometrical structures to any set of $D$ finite-dimensional hermitian matrices $X^a, \ a=1,...,D$. This framework generalizes and systematizes the well-known examples of fuzzy spaces, and allows to extract the underlying classical space without requiring the limit of large matrices or representation theory. The approach is based on the previously introduced concept of quasi-coherent states. In particular, a concept of quantum Kähler geometry arises naturally, which includes the well-known quantized coadjoint orbits such as the fuzzy sphere $S^2_N$ and fuzzy $\mathbb{C} P^n_N$. A quantization map for quantum Kähler geometries is established. Some examples of quantum geometries which are not Kähler are identified, including the minimal fuzzy torus.

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