Let
X
X
be a smooth projective variety over an algebraically closed field, and
f
:
X
→
X
f\colon X\to X
a surjective self-morphism of
X
X
. The
i
i
-th cohomological dynamical degree
χ
i
(
f
)
\chi _i(f)
is defined as the spectral radius of the pullback
f
∗
f^{*}
on the étale cohomology group
H
e
´
t
i
(
X
,
Q
ℓ
)
H^i_{\acute {\mathrm {e}}\mathrm {t}}(X, \mathbf {Q}_\ell )
and the
k
k
-th numerical dynamical degree
λ
k
(
f
)
\lambda _k(f)
as the spectral radius of the pullback
f
∗
f^{*}
on the vector space
N
k
(
X
)
R
\mathsf {N}^k(X)_{\mathbf {R}}
of real algebraic cycles of codimension
k
k
on
X
X
modulo numerical equivalence. Truong conjectured that
χ
2
k
(
f
)
=
λ
k
(
f
)
\chi _{2k}(f) = \lambda _k(f)
for all
0
≤
k
≤
dim
X
0 \le k \le \dim X
as a generalization of Weil’s Riemann hypothesis. We prove this conjecture in the case of abelian varieties. In the course of the proof we also obtain a new parity result on the eigenvalues of self-maps of abelian varieties in prime characteristic, which is of independent interest.