Luke 16:26
And beside all this, between us and you there is a great gulf fixed: so that they which would pass from hence to you cannot; neither can they pass to us, that would come from thence.
I’m one who thinks that of the psychic/spiritual phenomena that cannot be explained, “ghosts” are not the spirits of people—who, as you show from Luke 16:26 cannot come back... but rather demonic forces, which enjoy negative human reactions—or perhaps recreate evil memories they inspired.
NOT an area to go poking into (like the multitude of stupid “ghost hunter” TV shows today).