XV: The eXtended meta-uni-omni-Verse: Introduction, Taxonomy, and State-of-the-Art

The term "Virtual Reality'' (VR) has been in use since 1938, but the recent barrage of jargon, confusing new terminology, and the hype around VR and a plethora of related realities (AR, MR, etc.) have made it necessary to bring some order to the "Realities''; in fact, it has been largely recognized that there are a lot of "grey'' areas between the Realities, making it desirable to embrace an overarching vision. Throughout the world, many have chosen to use the framework of eXtended Reality (XR) as this unifying overarching concept to interpolate between the "Realities'' and to eXtrapolate beyond them. Together with XR, there is also XI (eXtended Intelligence) for which the IEEE has convened the Council on eXtended Inteligence, or CXI. A related concept is the metaverse, i.e. shared VR, introduced in 1974 as "Metavision'' and "Metaveillance'' and recently popularized by Facebook. In this paper we propose XV as an overarching term, concept, and taxonomy for shared (social) XR across all of the "Verses'', including the universe (physical reality, i.e. "atoms''), the metaverse (virtuality, i.e. "bits''), the omniverse and multiverse, etc.  We also briefly outline the state-of-the-art in the various realties and verses covered by XV.