English

Transformation properties for Dyson's rank function

Number Theory 2016-09-09 v2

Abstract

At the 1987 Ramanujan Centenary meeting Dyson asked for a coherent group-theoretical structure for Ramanujan's mock theta functions analogous to Hecke's theory of modular forms. Many of Ramanujan's mock theta functions can be written in terms of R(ζ,q)R(\zeta,q), where R(z,q)R(z,q) is the two-variable generating function of Dyson's rank function and ζ\zeta is a root of unity. Building on earlier work of Watson, Zwegers, Gordon and McIntosh, and motivated by Dyson's question, Bringmann, Ono and Rhoades studied transformation properties of R(ζ,q)R(\zeta,q). In this paper we strengthen and extend the results of Bringmann, Rhoades and Ono, and the later work of Ahlgren and Treneer. As an application we give a new proof of Dyson's rank conjecture and show that Ramanujan's Dyson rank identity modulo 55 from the Lost Notebook has an analogue for all primes greater than 33. The proof of this analogue was inspired by recent work of Jennings-Shaffer on overpartition rank differences mod 77.

Keywords

Cite

@article{arxiv.1601.05781,
  title  = {Transformation properties for Dyson's rank function},
  author = {Frank Garvan},
  journal= {arXiv preprint arXiv:1601.05781},
  year   = {2016}
}

Comments

I have corrected some typos from the previous version and added and clarified some material. I thank Chris Jennings-Shaffer, Eric Mortenson and Nick Andersen for their comments. Any additional comments or corrections are welcome

R2 v1 2026-06-22T12:34:26.779Z