• DOI:10.4310/CNTP.2017.v11.n2.a4
• Corpus ID: 59391085

On the Rankin-Selberg method for higher genus string amplitudes

@article{Florakis2016OnTR,
  title={On the Rankin-Selberg method for higher genus string amplitudes},
  author={Ioannis Florakis and Boris Pioline},
  journal={Communications in Number Theory and Physics},
  year={2016},
  volume={11},
  pages={337-404}
}

• I. Florakis, B. Pioline
• Published 31 January 2016
• Mathematics
• Communications in Number Theory and Physics

Closed string amplitudes at genus $h\leq 3$ are given by integrals of Siegel modular functions on a fundamental domain of the Siegel upper half-plane. When the integrand is of rapid decay near the cusps, the integral can be computed by the Rankin-Selberg method, which consists of inserting an Eisenstein series $E_h(s)$ in the integrand, computing the integral by the orbit method, and finally extracting the residue at a suitable value of $s$. String amplitudes, however, typically involve integrands with polynomial or even exponential growth at the cusps, and a renormalization scheme is required to treat infrared divergences. Generalizing Zagier's extension of the Rankin-Selberg method at genus one, we develop the Rankin-Selberg method for Siegel modular functions of degree 2 and 3 with polynomial growth near the cusps. In particular, we show that the renormalized modular integral of the Siegel-Narain partition function of an even self-dual lattice of signature $(d,d)$ is proportional to a residue of the Langlands-Eisenstein series attached to the $h$-th antisymmetric tensor representation of the T-duality group $O(d,d,Z)$.