Polygraph (mathematics)

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In mathematics, and particularly in category theory, a polygraph is a generalisation of a directed graph. It is also known as a computad. They were introduced as "polygraphs" by Albert Burroni [1] and as "computads" by Ross Street. [2]

In the same way that a directed multigraph can freely generate a category, an n-computad is the "most general" structure which can generate a free n-category. [3]

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A polygraph is a forensic instrument.

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References

  1. A. Burroni. Higher-dimensional word problems with applications to equational logic. TCS, 115(1):43--62, 1993.
  2. R. Street. Limits indexed by category-valued 2-functors. Journal of Pure and Applied Algebra, 8(2):149--181, 1976.
  3. computad at the nLab