This tentative paper first examines the question of a possible in-teraction between two large particles (not in contact) embedded in a sea of smaller monodisperse granular particles. Dealing with bidimensional config-urations, it is seen that the lowest energy state of such a piling corresponds to a regular triangular array locally distorted by the intruders. The defect clouds above both intruders intersect, giving rise to a potential energy de-pendence on distance. This results in an attractive force when the intruders are separated by distances of the order of their radius, whereas a repulsive force arises when the intruders are sitting far apart. The relationship of these findings with the problem of polymeric stabilization by depletion of colloidal dispersions is mentioned.
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