Dimension-free estimates for semi-commutative discrete Hardy-Littlewood maximal operators

For $2\le p\le \mathrm{\infty }$, we establish dimension-free estimates for discrete dyadic Hardy-Littlewood maximal operators over Euclidean balls on semi-commutative $L_p$ space. In particular, when the radius is sufficiently large, these operators admit dimension-free $L_p$ bounds for all $1<p<\mathrm{\infty }$. As applications, we derive the corresponding maximal ergodic inequalities and the bilaterally almost uniform convergence.