Tachyon, particles which moves faster than 3 * 108 m/s, nothing but particle that can move faster than light.
I heard about it for the first time, when I was doing my under graduation in physics, during a lecture given by a chemistry research analyst in South India.
‘tachyon’ (from the Greek ‘tachys,’ meaning swift)
So if there is a particle that can travel faster than light, it should have negative mass, which is imaginary! Can there be a particle which has a negative mass?
In a Lorentz invariant theory, the same formulas that apply to ordinary slower-than-light particles (sometimes called “bradyons” in discussions of tachyons) must also apply to tachyons. In particular the energy–momentum relation:
(where p is the relativistic momentum of the bradyon and m is its rest mass) should still apply, along with the formula for the total energy of a particle:
This equation shows that the total energy of a particle (bradyon or tachyon) contains a contribution from its rest mass (the “rest mass–energy”) and a contribution from its motion, the kinetic energy. When v is larger than c, the denominator in the equation for the energy is “imaginary”, as the value under the radical is negative. Because the total energy must be real,the numerator must also be imaginary: i.e. the rest mass m must be imaginary, as a pure imaginary number divided by another pure imaginary number is a real number.
In some modern formulations of the theory, the mass of tachyons is regarded as real
First check the “Measurement of the Single-Photon Tunneling Time” in the article below, the tunnel effect happens faster than light
Also good to check, High-Visibility Interference in a Bell-Inequality Experiment for Energy and Time
Third one to refer the article on tachyonlike excitations
@ This information of this article is written from various science article, with some own information, also with some reference from wikipedia