Is the key of the ghost imaging mystery given by the electromagnetic crossing symmetric photon reactions?

In the ghost imaging system, the object and image are separately illuminated by a pair of correlated beams and the image is obtained through coincidence detection of the two beams. When the correlated beams are obtained by a spontaneous parametric down-conversion phenomenon, the image formation is attributed to either quantum entanglement or wave vector correlation. The physicist D B Ion has published a different point of view: the ghost imaging can be explained by electromagnetic crossing symmetric photon reactions. We report on an experimental setup to verify that a change of the object reflection coefficient modifies the idler single count rate. The obtained results are a confirmation proof and suggest the existence of a stimulated spontaneous parametric down-conversion effect. A possible application is mentioned. (paper)