Void-Supercluster Alignments

We investigate alignments between the spin axes of cosmic voids and the principal axes of nearby superclusters using the Millennium Run simulation of a LCDM cosmology. The concept of void spin was first introduced by Lee and Park in 2006 to quantify the tidal effect on voids from the surrounding matter distribution. Our numerical analysis reveals that the void spin axes are strongly aligned with the supercluster minor axes, but anti-aligned with the major axes, and have no correlations with the intermediate axes. We provide physical explanations to this numerical results on the basis of tidally induced correlations. It is expected that our work will provide a new insight into the characterization of the cosmic web on the largest scale.