Fundamental interaction and the strong interaction. Their magnitude and behaviour vary greatly, as described in the table below. Modern physics attempts to explain every observed physical phenomenon by these fundamental interactions. Moreover, reducing the number of different interaction types is seen as desirable. Two cases in point are the unification of: Both magnitude ("relative strength") and "range", as given in the table, are meaningful only within a rather complex theoretical framework. It should also be noted that the table below lists properties of a conceptual scheme that is still the subject of ongoing research. The modern (perturbative) quantum mechanical view of the
Non-physical entity a ghost that makes it a specifically non-physical, rather than a physical entity. Were the existence of ghosts ever demonstrated beyond doubt, it has been claimed that would actually place them in the category of "physical" entities. Purported non-mental non-physical entities include things such as gods, angels, demons, and ghosts. Lacking demonstrations of their existence, their existences and natures are widely debated, independently of the philosophy of mind. Non-physical entity In ontology and the philosophy of mind, a non-physical entity is a spirit or being that exists outside physical reality. Their existence divides the philosophical school of physicalism from the