SI base unit SI base unit The International System of Units (SI) defines seven units of measure as a basic set from which all other SI units can be derived. The SI base units and their physical quantities are the meter for measurement of length, the kilogram for mass, the second for time, the ampere for electric current, the kelvin for temperature, the candela for luminous intensity, and the mole for amount of substance. The SI base units form a set of mutually independent dimensions as required by dimensional analysis commonly employed in science and technology. The names and symbols of SI base
Cartan formalism (physics) the normal Einstein–Hilbert action, using the relations formula_95 and formula_96. Note that in terms of the Planck mass, we set formula_97, whereas the last term keeps all the SI unit factors. Note that in the presence of spinor fields, the Palatini action implies that formula_98 is nonzero. So there's a non-zero torsion, i.e. that formula_99. See Einstein–Cartan theory. Cartan formalism (physics) The vierbein or tetrad theory much used in theoretical physics is a special case of the application of Cartan connection in four-dimensional manifolds. It applies to metrics of any signature. (See metric tensor.) This section is an approach to