  We show that a differential structure associated with the infinite particle
Dyson Brownian motion satisfies the Bakry-\'Emery nonnegative lower Ricci
curvature bound $\mathsf{BE}(0, \infty)$. Various functional inequalities
follow including a local spectral gap inequality, the Lipschitz Feller
property, the dimension-free Harnack inequality and the evolutional variation
inequality. As a consequence, the infinite Dyson Brownian motion is
characterised as a gradient flow of the Boltzmann-Shannon entropy associated
with $\mathsf{sine}_\beta$ point processes with respect to a certain
Benamou-Brenier-like Wasserstein distance. At the end, we provide a sufficient
condition for $\mathsf{BE}(K, \infty)$ beyond the Dyson model and apply it to
the infinite particle model of the $\beta$-Riesz gas.
