= Solution
\b[Yes, at the weak-field accuracy of the experiment.] The <Pound-Rebka experiment> measures <gravitational redshift>, which <Nordstrom theory of gravitation> predicts even though it does not predict bending of light.
In a static field, a stationary clock has $d\tau=\phi\,dt$. A <photon> has constant <Killing energy> $E=-p_t$, and an observer at rest has $U=\phi^{-1}\partial_t$. Its measured frequency is proportional to $-p_iU^i=E/\phi$. Emission at $e$ and reception at $r$ therefore give
$$
\boxed{\frac{\nu_r}{\nu_e}=\frac{\phi_e}{\phi_r}
=1+\Phi_e-\Phi_r+O(\Phi^2).}
$$
An upward ray has $\Phi_r-\Phi_e\simeq gH/c^2$ when ordinary units are restored, so $\Delta\nu/\nu\simeq-gH/c^2$. This is the shift tested using the <Mössbauer effect>. The <gravitational redshift> follows from the physical clock rates; a claim that straight light paths imply no frequency shift would confuse two different observables.
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