Rotation of Cosmic Voids and Void Spin Statistics

We present a theoretical study of void spins and their correlationproperties. The concept of the spin angular momentum for an unbound void isintroduced to quantify the effect of the tidal field on the distribution ofmatter that make up the void. Both the analytical and numerical approaches areused for our study. Analytically, we adopt the linear tidal torque model toevaluate the void spin-spin and spin-density correlations, assuming that a voidforms in the initial region where the inertia momentum and the tidal sheartensors are maximally uncorrelated with each other. Numerically, we use theMillennium run galaxy catalog to find voids and calculate their spinstatistics. The numerical results turn out to be in excellent agreement withthe analytic predictions, both of which consistently show that there are strongspatial alignments between the spin axes of neighbor voids and stronganti-alignments between the void spin axes and the directions to the nearestvoids. We expect that our work will provide a deeper insight into the originand properties of voids and the large scale structure.Comment: accepted version, ApJ in press, the concept of void spins explained, typos correcte