Large Extra Dimension Effects on the Spin Configuration of the Top Quark Pair at $e^{+}e^{-}$ Colliders

Large extra dimension effects on the spin configuration of the top quark pair at the $e^+ e^-\to t\bar{t}$ process are studied. It is shown that the TeV scale quantum gravity effects cause significant deviations from the Standard Model predictions for the spin configuration in the off-diagonal basis: they lead to substantial cross sections of the like-spin states of the top quark pair, which vanish in the SM; they weaken the pure dominance of the processes, the Up-Down (Down-Up) spin states for the left-handed (right-handed) beam. In addition for the unlike-spin states in some region of the top scattering angle, the destructive interference between the Kaluza-Klein graviton mediated diagram and the SM ones takes place