In 1962, three Indians
Came up with their theoretical framework ‘meta particle’. A hypothetical particle travelling beyond the speed of light. In 1967, Gerald Feinberg published a reach-paper, named ‘tachyon particle’.
The mathematical and theoretical existence of tachyons breaks causality principle, which says cause will always be ahead of the effect.
Let me explain to you how
A glass fell down and broke. Because a glass fell down is a cause and broke is the effect.
Many of us have a misconception that Einstein’s theory of relativity restricts speed limit i.e nothing can exceed the speed of light instead theory predicts, it’s impossible for a body having mass to travel faster than the speed of light as it requires infinite amount of energy with a Technicality, if a body travels lower than the speed of light it will remain travelling lower than that and if traveling faster then speed of light then it will remain travelling faster than that
but there is no observable evidence till now. Therefore, tachyons would not violate the theory of relativity and would possess properties such as
Relativistic length, mass and lifespan would be imaginary
If V>C assuming √-1=i for the cancellation rest mass should be imaginary
Infinite amount of energy is required to accelerate a particle with mass but in contrary, tachyons would lose energy and speed would gradually increase. At the time of energy=0, the speed would be infinite. Moreover, On supplying energy their speed would slow down since tachyons posses negative energy.
The tachyonic Antitelphonic device would come into existence through it we could easily send messages to our past. Although this device would allow you to communicate faster than the speed of light but time would also play its role, it would gradually move backwards. Suppose you send a message ‘how are you’ to your friend on another planet which is 10,000 light years away from earth. So, with the help tachyonicnic device, message travelled faster than the speed of light and because time reversed. He received your message before you have actually sent it. Hence, you would get the reply ‘I am fine’ before you send ‘how are you’. This would lead to past time-traveling paradoxes.
Bosonic string theory’s mathematical equations also predict the existence of fundamentally unstable particle tachyon. CERN in September 2011 announced that they have found tau neutrino travelling faster than the speed of light which was then concluded to be an error in calculations due to defect in fibre optic.