Electrostatic interactions of charged bodies from the weak- to the strong-coupling regime

A simple field theory approach is developed to model the propertiesof charged, dielectric bodies and their associated counterions. Thispredictive theory is able to accurately describe the properties ofsystems (as compared to computer simulation data) from the weak-couplinglimit, where the Poisson-Boltzmann theory works well, through tothe strong-coupling limit. In particular, it is able to quantitativelydescribe the attraction between like-charged plates. In addition,the theory remains accurate even in the presence of dielectric bodies,properly accounting for the influence of image charge interactions.The theory is compared to the strong-coupling expansion, which isfound to be applicable only in certain limited situations when dielectricvariations are present.