Go beyond ghosts and into the realm of quantum physics. In these cases , twopeople see each other simultaneously through some anomoly in time. Each person appears as a ghost to the other, and both are equally surprised by the event. In a reciprocal apparition, you, as the viewer, might perceive a gentleman, dressed in antique garb, going about his business, who then glances up, and with an astonished look on his face, sees you as well. Both you and he are puzzled, as you both are “out of place” to the eyes of the other. These apparitions usually are short-lived and if you but glance away, the vision vanishes.
