Quantum theory requires gravity and superrelativity
  The ordinary quantum theory points out that general relativity is negligible for spatial distances up to the Planck scale. Consistency in the foundations of the quantum theory requires a``soft'' spacetime structure of the general relativity at essentially longer length. However, for some reasons this appears to be not enough. A new framework (``superrelativity'') for the desirable generalization of the foundation of quantum theory is proposed. A generalized non-linear Klein-Gordon equation has been derived in order to shape a stable wave packet. 
Peter Leifer