#### Bulg. J. Phys. vol.35 no.s1 (2008), pp. 323-328

#### Noncommutative Spacetime and Emergent Gravity

Hyun Seok Yang

go back^{1,2}^{1}*School of Physics, Korea Institute for Advanced Study, Seoul 130-012, Korea*^{2}*Institut für Physik, Humboldt Universität zu Berlin, Newtonstraße 15, D-12489 Berlin, Germany*Abstract.We argue that a field theory defined on noncommutative (NC) spacetime should be regarded as a theory of gravity, which we refer to as the emergent gravity. A whole point of the emergent gravity is essentially originated from the basic property: A NC spacetime is a (NC) phase space. This fact leads to two important consequences:

(I) A NC field theory can basically be identified with a matrix model or a largeNfield theory where NC fields can be regarded as master fields of largeNmatrices.

(II) NC fields essentially define vector (tetrad) fields. So they define a gravitational metric of some manifold as an emergent geometry from NC gauge fields.

Of course, the pictures (I) and (II) should refer to the same physics, which should be familiar with the largeNduality in string theory. The1/Ncorrections in the picture (I) correspond to the derivative corrections in terms of the noncommutativity θ for the picture (II).