Proprietà di 20 ordine di un riferimento isotropo

We extend to the isotropic case, by adapted non-holonomic techniques 1], 2^° order properties of a relativistic frame of reference, generalized in the polar sense 2,3]: Riemann and gravitational tensors decomposition, Lie derivative of the Ricci rotation coefficients, commutation formulae and finally Bianchi identity. All the decomposition tensors are formally invariant (as regards the standard case), by means of the longitudinal derivative extension. Received: June 14, 2000?Published online: October 2, 2001