About A New Self-Tuning Mechanism in String Theory

Submit Manuscript | http://medcraveonline.com cosmological constant λ is directly determined from the scalar potential scalar  alone (see for instance [2,3]). In the self-tuning mechanism λ contains a supersymmetry breaking term SB  besides the usual scalar  of the =1 N super gravity and where SB  has its own gauge arbitrariness. Also in this mechanism, whether λ vanishes or not is basically determined by the tensor structure of scalar  , not by the zero or nonzero values of scalar  itself, unlikely to the ordinary theories. In [1], this self-tuning mechanism has been applied to the well-known KKLT model [3] and it was shown that λ must be fine-tuned to zero =0 λ , at the supergravity level.