A Tachyonic Model of Dark Matter

Tachyons, faster-than-light particles, are proposed as a candidate for dark matter. Extended special relativity theory shows that tachyons can exist but cannot interconvert with regular matter (bradyons). Tachyons may interact with each other and with dark, or tachyonic, photons; but not via conventional electromagnetic radiation. Tachyonic matter interacts only gravitationally with bradyons which is compatible with the observed properties of dark matter. The likely nature of tachyonic dark matter is a diffuse medium. Extending the Dirac equation to tachyonic matter indicates that electrons, protons, etc. have tachyonic counterparts. Therefore, tachyonic matter is likely to be similar to the primordial intergalactic medium comprising mostly of hydrogen and helium. Extended special relativity is used to show that matter cannot travel backwards in time. Information could be transmitted backwards in time using gravitational attraction between bradyons and tachyons, but this is so impractical that it is effectively impossible.