Given a pure motive
over
with a multilinear
algebraic structure
on
, and given a
representation
of the group
respecting
, we describe
a functorial transfer
.
We formulate a criterion that guarantees when the two periods of
are equal. This has an implication for the critical values of the
-function attached
to
. The criterion
is explicated in a variety of examples such as: tensor product motives and Rankin–Selberg
-functions; orthogonal motives
and the standard
-function
for even orthogonal groups; twisted tensor motives and Asai
-functions.
Keywords
periods of motives, special values of $L$-functions,
Langlands functoriality