Dressed coordinates: the path-integrals approach
  The recent introduced \textit{dressed coordinates} are studied in the path-integral approach. These coordinates are defined in the context of a harmonic oscillator linearly coupled to massless scalar field and, it is shown that in this model the dressed coordinates appear as a coordinate transformation preserving the path-integral functional measure. The analysis also generalizes the \textit{sum rules} established in a previous work. 
R. Casana, G. Flores-Hidalgo and B. M. Pimentel