Getting to the top with extra dimensions
  The prospect of large extra dimensions and an effective theory of gravity at around a TeV has interesting experimental consequences. In these models, the Kaluza-Klein modes interact with Standard Model particles and these interactions lead to testable predictions at present and planned colliders. We investigate the effect of virtual exchanges of the spin-2 Kaluza-Klein modes in the production cross-section of $t \bar t$ pairs at the Tevatron and the LHC and find that the $t \bar t$ cross-section can be an effective probe of the large extra dimensions. This enables us to put bounds on the effective low-energy scale. 
Prakash Mathews, Sreerup Raychaudhuri and K. Sridhar (TIFR)