Correlations of cosmic tidal fields

We study correlations amongst tidal fields originated by the large-scale di stribution of matter in the Universe. The two-point tidal correlation is de scribed as a rank-4 tensor, the elements of which can be written in terms o f four fundamental scalar functions ranging, with respect to the spatial se paration, from purely transversal to purely longitudinal correlations. Tida l fields, on both galaxy and cluster scales, are revealed to be correlated over distances larger than the mass-density correlation length, although tr aceless tidal fields show anticorrelation between diagonal terms along orth ogonal directions. The cross-correlation between mass and tidal field is al so analysed. These results are relevant for galaxy formation and the interp retation of large-scale weak lensing phenomena.