Ionization energy The sciences of physics and chemistry use different measures of ionization energy. In physics, the unit is the amount of energy required to remove a single electron from a single atom or molecule, expressed as electronvolts. In chemistry, the unit is the amount of energy required for all of the atoms in a mole of substance to lose one electron each: molar ionization energy or enthalpy, expressed as kilojoules per mole (kJ/mol) or kilocalories per mole (kcal/mol). Comparison of "E" of elements in the periodic table reveals two periodic trends: The latter trend results from the outer electron shell being
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