Dirac equation in the algebra of physical space Dirac equation in the algebra of physical space The Dirac equation, as the relativistic equation that describes spin 1/2 particles in quantum mechanics, can be written in terms of the Algebra of physical space (APS), which is a case of a Clifford algebra or geometric algebra that is based on the use of paravectors. The Dirac equation in APS, including the electromagnetic interaction, reads Another form of the Dirac equation in terms of the Space time algebra was given earlier by David Hestenes. In general, the Dirac equation in the formalism of geometric algebra has the advantage of providing a
N-entity the lowest, "i.e.", the physical layer, to the highest, so that the -th layer is above the "n"-th layer and the -th layer is below. N-entity In telecommunication, a "n"-entity is an active element in the "n"-th layer of the Open Systems Interconnection--Reference Model (OSI-RM) that (a) interacts directly with elements, "i.e.", entities, of the layer immediately above or below the "n"-th layer, (b) is defined by a unique set of rules, "i.e.", syntax, and information formats, including data and control formats, and (c) performs a defined set of functions. The "n" refers to any one of the 7 layers