The energy and momentum content of an electromagnetic field can be expressed entirely in terms of the fields through the energy-momentum tensor with no mention of the sources creating the fields. This tensor is defined such that chiral currents are introduced. In the case of free force we have <img border=0 width=44 height=19 src="/fbpe/img/ingeniare/v16nespecial/image03-1.gif">and <img border=0 width=56 height=16 src="/fbpe/img/ingeniare/v16nespecial/image03-2.gif">. This approach allows for a very symmetric derivation of the energy and momentum content of the fields with <img border=0 width=36 height=17 src="/fbpe/img/ingeniare/v16nespecial/image03-3.gif">. This configuration is essential to the unification of electromagnetism and gravity, obtaining a force-free configuration for the electron. To obtain this unification the Rainich geometrization under chiral conditions is discussed.