Fringe science is scientific inquiry in an established field of study that departs significantly from mainstream or orthodox theory, and is classified in the “fringes” of a credible mainstream academic disciplines.
Three classifications of scientific ideas have been identified (center, frontier, fringe) with mainstream scientists typically regarding fringe concepts as highly speculative or even strongly refuted.
A particular concept that was once accepted by the mainstream scientific community can become ”fringe science” due to a later evaluation of previously supportive research. For example focal infection theory (the idea that focal infections of the tonsils or teeth were a primary cause of systemic disease) was once considered medical fact, but is now dismissed due to lack of evidence. Conversely, fringe science can include novel proposals and interpretations that initially have only a few supporters and much opposition. Some theories which were developed on the fringes (for example, continental drift, existence of Troy, heliocentrism, the Norse colonization of the Americas, and Big Bang Theory have become mainstream due to the discovery of supportive evidence.
Fringe science covers everything from novel hypotheses that can be tested via scientific Method to wild theories and “New Age mumbo jumbo” with the dominance of the latter resulting in the tendency to dismiss ”all” fringe science as the domain of pseudoscience, hobbyists, or quacks. Other terms used for the portions of fringe science that lack scientific integrity are ”pathological science”, ”voodoo science”, and ”cargo cult science”. ”Junk science” is a term typically used in the political arena to describe ideas that proponents erroneously, for political reasons, dubiously or even fraudulently claim scientific backing.
In the philosophy of science, the question of where to properly draw a boundary between science and non-science, when the objective actually is objectivity, is called the demarcation problem. Compounding this issue is that proponents of some fringe theories use both proper scientific evidence and outlandish claims to support their arguments.