3 5 0 D O C . 3 6 8 O N U N I F I E D F I E L D T H E O R Y … (3) … (4) where and are abbreviations for the expressions in brackets. These two Furthermore, one obtains by Owing to (2), these two expressions are related to the quantities introduced in (1) by the identity In addition, by applying (5 1.c) to the purely antisymmetric quantities introduced in (1) (whose vanishing is nat- urally not yet presupposed here), one obtains the identity . …, (5) which is constructed analogously to (4). The tensor densities G, H and F are, owing to (2), related by the identity … (6) I then recall the tensor density and the identity that holds for it (cf. (3b) 1.c), … (2) Along with V, we now introduce the generalization of this quantity … (3) where presents an arbitrary, constant number. This quantity fulfills—as can be verified by twofold application of the divergence-commutation relation (5) 1.c— the two identities … (4) … (5) or, if one abbreviates the two expressions in brackets as and , … (4a) … (5a) In general, we use a dash above the symbol to indicate that the corresponding expression was formed using instead of . Making the transition to , which is carried out at the end of the calculations, can then be accom- plished by simply leaving off the dashes. If we now introduce the quantities (or ) defined in (1), which are of course initially not presumed to vanish, one can convince oneself by direct calculation that the identity , … (6) holds, where is defined by (1).[6] V / V    –   / G /  0  = V / 1 2 V    –    / H /  0  = G H S   S  S / 1 2 S    –    / F /  0  = G H + F 0  – [p. 3] V  V / 0  V  V          – –  – V  W  – = = V/  1 2 V   –    / H / 0  = V/  V/   –  V//  0  – H G H / 0  G /  V//  0  – V  V   0 = S  S  G H – 1 2 --S   0  – S  introduced (whose instead se presumed