Critical and Granular Casimir Forces: A Methodological Convergence from Nano to Macroscopic Scales

Recent advances in colloidal science that have lead to directly measuring depletion and critical Casimir interaction potentials are reviewed. Methodological convergence of these studies is exploited and extended to granular systems in order to measure effective interactions among their constituent particles. Experimental evidence of depletion interactions as well as a novel “granular Casimir effect” is presented and subtle differences are discussed.