Strings with Negative Stiffness and Hyperfine Structure

  title={Strings with Negative Stiffness and Hyperfine Structure},
  author={M. C. Diamantini and H. Kleinert and C. Trugenberger},
  journal={Physical Review Letters},
We propose a new string model by adding a higher-order gradient term to the rigid string, so that the stiffness can be positive or negative without loosing stability. In the large-D approximation, the model has three phases, one of which with a new type of generalized "antiferromagnetic" orientational correlations. We find an infrared-stable fixed point describing world-sheets with vanishing tension and Hausdorff dimension D_H=2. Crumpling is prevented by the new term which suppresses… Expand