English

A generalized PGL(2) Petersson/Bruggeman-Kuznetsov formula for analytic applications

Number Theory 2026-01-27 v3

Abstract

We develop generalized Petersson/Bruggeman-Kuznetsov (PBK) formulas for specified local components at non-archimedean places. In fact, we introduce two hypotheses on non-archimedean test function pairs fπ(f)f \leftrightarrow \pi(f), called geometric and spectral hypotheses, under which one obtains `nice' PBK formulas by the adelic relative trace function approach. Then, given a supercuspidal representation σ\sigma of PGL2(Qp){\rm PGL}_2(\mathbb{Q}_p), we study extensively the case that π(f)\pi(f) is a projection onto the line of the newform if π\pi is isomorphc to σ\sigma or its unramified quadratic twist, and π(f)=0\pi(f) = 0 otherwise. As a first application, we prove an optimal large sieve inequality for families of automorphic representations that arise in our framework.

Keywords

Cite

@article{arxiv.2411.05672,
  title  = {A generalized PGL(2) Petersson/Bruggeman-Kuznetsov formula for analytic applications},
  author = {Yueke Hu and Ian Petrow and Matthew P. Young},
  journal= {arXiv preprint arXiv:2411.05672},
  year   = {2026}
}

Comments

v3: Final accepted version. To appear in Forum Math. Sigma

R2 v1 2026-06-28T19:53:11.854Z