see: The Massless Axion-Higgs Vacuum Rigid String particle, even in Micro and Macro Dark Matter Black Hole Nuclei. see also: http://vixra.org/abs/1711.0443 or
https://www.researchgate.net/publication/323656594_The_New_Semi_Classical_Model_of_Quantum_FFF_Theory_based_on_Symmetric_Transformable_Entangled_Rigid_Strings