The centered logarithmic Brunn--Minkowski inequality

The logarithmic Brunn–Minkowski and logarithmic Minkowski inequalities are proved for convex bodies whose centroids are at the origin, with equality precisely for independent positive dilations of common direct summands. This characterizes when centered convex bodies have the same cone-volume measure. The $L_p$ Brunn–Minkowski and Minkowski inequalities are also obtained for every $p>0$, with equality only for positive dilates, and the corresponding uniqueness of centered $L_p$ surface area measures is established.