Look up the term ''Spectral evidence''. What does this term mean and what role did ''Spectral evidence'' play in the Salem Witch Trials?

"Spectral evidence refers to a witness testimony that the accused person's spirit or spectral shape appeared to him/her witness in a dream at the time the accused person's physical body was at another location. It was accepted in the courts during the Salem Witch Trials. The girls shrieking and changing temperature (they feel cold) when they pretend to see Mary Warren manifested as a bird is an example of this.