Top quark spin correlations in theories with large extra dimensions at the CERN Large Hadron Collider

In theories with large extra dimensions, we study the top-spin correlations at the Large Hadron Collider. The $s$-channel process mediated by graviton Kaluza-Klein modes contributes to the top-antitop pair production in addition to the standard model processes, and affects the resultant top-spin correlations. We calculated the full density matrix for the top-antitop pair production. With the fundamental scale of the extra dimensional theory below 2 TeV, we find a sizable deviation of the top-spin correlations from the standard model one.