Magnetic reluctanceMagnetic reluctance, or magnetic resistance, is a concept used in the analysis of magnetic circuits. It is defined as the ratio of magnetomotive force (mmf) to magnetic flux. It represents the opposition to magnetic flux, and depends on the geometry and composition of an object. Magnetic reluctance in a magnetic circuit is analogous to electrical resistance in an electrical circuit in that resistance is a measure of the opposition to the electric current. The definition of magnetic reluctance is analogous to Ohm's law in this respect.
Magic (illusion)Magic, which encompasses the subgenres of illusion, stage magic, and close-up magic, among others, is a performing art in which audiences are entertained by tricks, effects, or illusions of seemingly impossible feats, using natural means. It is to be distinguished from paranormal magic which are effects claimed to be created through supernatural means. It is one of the oldest performing arts in the world. Modern entertainment magic, as pioneered by 19th-century magician Jean-Eugène Robert-Houdin, has become a popular theatrical art form.
Geometric phaseIn classical and quantum mechanics, geometric phase is a phase difference acquired over the course of a cycle, when a system is subjected to cyclic adiabatic processes, which results from the geometrical properties of the parameter space of the Hamiltonian. The phenomenon was independently discovered by S. Pancharatnam (1956), in classical optics and by H. C. Longuet-Higgins (1958) in molecular physics; it was generalized by Michael Berry in (1984). It is also known as the Pancharatnam–Berry phase, Pancharatnam phase, or Berry phase.
Magic (supernatural)Magic, sometimes spelled magick, is an ancient practice rooted in rituals, spiritual divinations, and/or cultural lineage—with an intention to invoke, manipulate, or otherwise manifest supernatural forces, beings, or entities in the natural world. It is a categorical yet often ambiguous term which has been used to refer to a wide variety of beliefs and practices, frequently considered separate from both religion and science.
SupernaturalSupernatural refers to phenomena or entities that are beyond the laws of nature. The term is derived from Medieval Latin supernaturalis, from Latin super- (above, beyond, or outside of) + natura (nature). Though the corollary term "nature", has had multiple meanings since the ancient world, the term "supernatural" emerged in the Middle Ages and did not exist in the ancient world. The supernatural is featured in folklore and religious contexts, but can also feature as an explanation in more secular contexts, as in the cases of superstitions or belief in the paranormal.
