Non-critical string theory

The non-critical string theory describes the relativistic string without enforcing the critical dimension. Because in these cases, the non-critical string theory is not suitable to describe the fundamental nature of interactions, as it does not have the property of consistently quantized Lorenz symmetry and massless excitations. However, there are several applications for such a theory. The most prominent application is the phenomological description of the confinement of strong interaction by QCD strings. There also exists a duality to the 3-dimensional Ising model.