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
Physical intimacy Physical intimacy Physical intimacy is sensual proximity or touching. It is an act or reaction, such as an expression of feelings (including close friendship, platonic love, romantic love or sexual attraction), between people. Examples of physical intimacy include being inside someone's personal space, holding hands, hugging, kissing, caressing and sexual activity. Physical intimacy can often convey the real meaning or intention of an interaction in a way that accompanying speech simply cannot do. Physical intimacy can be exchanged between any people but as it is often used to communicate positive and intimate feelings, it most often occurs in people who