  The large difference between the Planck scale and the electroweak scale,
known as the hierarchy problem, has been addressed in some models through the
existence of extra spatial dimensions. A search for evidence of extra spatial
dimensions has been performed, through an analysis of the diphoton final state
in data recorded in 2011 with the ATLAS detector at the CERN Large Hadron
Collider. The analysis uses a dataset of 2.12 fb-1 of proton-proton collisions
at sqrts=7 TeV. The diphoton invariant mass spectrum is observed to be in good
agreement with the expected Standard Model (SM) background. We set 95 CL lower
limits on the fundamental Planck scale in the context of the Arkani-Hamed,
Dimopoulos, Dvali model (ADD) and on the lightest Kaluza Klein (KK) excitation
mass in the context of the Randall-Sundrum model (RS).
