Abstract
Abstract
In this paper, we prove uniform bounds for
$\operatorname {GL}(3)\times \operatorname {GL}(2) \ L$
-functions in the
$\operatorname {GL}(2)$
spectral aspect and the t aspect by a delta method. More precisely, let
$\phi $
be a Hecke–Maass cusp form for
$\operatorname {SL}(3,\mathbb {Z})$
and f a Hecke–Maass cusp form for
$\operatorname {SL}(2,\mathbb {Z})$
with the spectral parameter
$t_f$
. Then for
$t\in \mathbb {R}$
and any
$\varepsilon>0$
, we have
$$\begin{align*}L(1/2+it,\phi\times f) \ll_{\phi,\varepsilon} (t_f+|t|)^{27/20+\varepsilon}. \end{align*}$$
Moreover, we get subconvexity bounds for
$L(1/2+it,\phi \times f)$
whenever
$|t|-t_f \gg (|t|+t_f)^{3/5+\varepsilon }$
.
Funder
National Key Research and Development Program of China
National Natural Science Foundation of China
Publisher
Cambridge University Press (CUP)