Trivially easy for a real scientist with all the equipment perhaps. Does anyone care enough to do the experiment? I can't think of any funding that has been earmarked for disproving the existence of ghosts. No one wants to spend money on that. There are real problems that need solving. Besides, if it was shown to be possible, there would still be people saying that their ghost was a REAL ghost.
I am just throwing out ideas for fun, and people are seeing something... There has to a logical explanation.
DD