ON THE DERIVATION OF THE STRING EFFECTIVE ACTION FROM AN ACCELERATIONFIELD

We show that the string cosmology with dilaton can be derived, as a sp ecial case, from Caianiello's model of General Relativity with maximal acceleration interpreting the dilaton as an acceleration field. In fa ct Caianiello's theory allows us to recover the string-dilation effect ive action starting from a gravitational action which is minimally cou pled to a scalar field by means of a particular conformal transformati on of the Friedman-Robertson-Walker (FRW) metric. We show that this sc heme works near the Planck scale where the pure string-dilaton dynamic s works.