First mentioned by Dr. Edgar Allan in a G+ post.
Johnathan Chung summarizes the references and thoughts on Exotic Essence here (quote from his comment)
Johnathan Chung Mar 5, 2013
It's interesting that Niantic researchers attribute the theory of “exotic essence” to Dr. Lynton-Wolfe. It sounds similar to Dr. +Edgar Allan Wright's hypothesis that “people leave bits of themselves in places that are important to them”, which was explained in a chat log from Jan.29th when discussing the outcome of the Cahokia Mounds event with Hank Johnson. http://commondatastorage.googleapis.com/pac/IB/02/item/vulnerable.html
It also sounds similar to Wright's theories on the “complex relationship of Exotic Matter, alignment, human action, fictional creation and fate change… Future events are a function of Fate + Will x XM.”
Apparently, the term “exotic essence” was first mentioned by Wright in one of his Google+ comments on Feb.10th in reference to the fact that it was Jarvis' exotic essence that appeared at Cupid's Span (and more recently at Wallace Monument).
Dr. Wright explained that these events of “vulnerability” (i.e., the window of influence for field agents to control specific portals linked to sensitives like Hank Johnson, Klue, and now Misty) require precursor events. He further stated that someone has already isolated the ability to spot these precursors and to predict these linkages, and that Dr. Kureze himself may be monitoring these portals of interest. Perhaps this is how the NIA plans to gain control of sensitives and citizens–by leveraging XM entanglement.