Q-theta function

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In mathematics, the q-theta function (or modified Jacobi theta function) is a type of q-series which is used to define elliptic hypergeometric series. [1] [2] It is given by

where one takes 0  |q| < 1. It obeys the identities

It may also be expressed as:

where is the q-Pochhammer symbol.

See also

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References

  1. Gasper, G., Rahman, M. (2004). Basic hypergeometric series. Cambridge university press.
  2. Spiridonov, V. P. (2008). Essays on the theory of elliptic hypergeometric functions. Russian Mathematical Surveys, 63(3), 405.