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PlanetPhysics/Fundamental Quantum Groupoid

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A fundamental quantum groupoid   is defined as a functor , where  is the category of Hilbert space bundles, and  is the category of quantum groupoids and their homomorphisms.

Fundamental Groupoid Functors and Functor Categories

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The natural setting for the definition of a quantum fundamental groupoid is in one of the functor categories-- that of fundamental groupoid functors, Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "http://localhost:6011/en.wikiversity.org/v1/":): {\displaystyle F_{\grp}} , and their natural transformations defined in the context of quantum categories of quantum spaces represented by Hilbert space bundles or `rigged' Hilbert (or Frech\'et) spaces .

Other related functor categories are those specified with the general definition of the fundamental groupoid functor, Failed to parse (unknown function "\grp"): {\displaystyle F_{\grp}: '''Top''' \to \grp_2} , where Top is the category of topological spaces and Failed to parse (unknown function "\grp"): {\displaystyle \grp_2} is the groupoid category.

A specific example of a quantum fundamental groupoid can be given for spin foams of spin networks, with a spin foam defined as a functor between spin network categories. Thus, because spin networks or graphs are specialized one-dimensional CW-complexes whose cells are linked quantum spin states, their quantum fundamental groupoid is defined as a functor representation of CW-complexes on `rigged' Hilbert spaces (also called Frech\'et nuclear spaces).