Entities perceived during DMT inebriation have been represented in diverse forms of psychedelic art. The term "machine elf" was coined by ethnobotanist Terence McKenna for the entities he encountered in DMT "hyperspace", also using terms like "fractal elves", or "self-transforming machine elves". McKenna first encountered the "machine elves" after smoking DMT in Berkeley in 1965. His subsequent speculations regarding the hyperdimensional space in which they were encountered have inspired a great many artists and musicians, and the meaning of DMT entities has been a subject of considerable debate among participants in a networked cultural underground, enthused by McKenna's effusive accounts of DMT hyperspace. Cliff Pickover has also written about the "machine elf" experience, in the book "Sex, Drugs, Einstein, & Elves", while Rick Strassman notes many similarities between self-reports of his DMT study participants' encounters with these "entities", and mythological descriptions of figures such as Chayot Ha Kodesh in Ancient religions, including both angels and demons. Strassman also argues for a similarity in his study participants' descriptions of mechanized wheels, gears and machinery in these encounters, with those described in visions of encounters with the Living Creatures and Ophanim of the Hebrew Bible, noting they may stem from a common neuropsychopharmacological experience.