Superluminal Particles, Cosmology and Cosmic-Ray Physics
  Non-tachyonic superluminal sectors of matter (superbradyons), with critical speeds in vacuum much larger than the speed of light, can quite naturally exist and play an important role in both cosmic-ray physics (anomalous high-energy events) and cosmology (big-bang physics, alternatives to inflation, dark matter...). They can even be the real "elementary" particles. An updated discussion of the subject is presented, in relation with recent theoretical and experimental results. Prospects for future searches are also reexamined. Lorentz symmetry violation (LSV) models based on mixing with superbradyons are compared with LDRK (linearly deformed relativistic kinematics) and QDRK (quadratically deformed relativistic kinematics) such as defined in our previous paper physics/0003080 . 
Luis Gonzalez-Mestres