Negative Mass Particles: Will They Reach Infinite Speed?

Garlic
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Hello,
I heard that theoretical particles that have negative mass (techyons) are predicted to tend to speed up to infinite, if their energies are low enough. I don't understand why infinite speed instead of 2c (double the speed of light) are predicted?
Note: I don't know whose/which theory it is. Sorry if my question is irrelevant.
Thank you
 
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Garlic said:
negative mass (techyons)
Tachyons have negative squared masses.

Why would you think that the speed should be 2c for a low energy tachyon? Generally, for any particle, ##v = pc^2/E##. All particles satisfy ##E^2 = (pc)^2 + (mc^2)^2## and so if the tachyon has negative mass squared, the energy of the tachyon can be zero. Its velocity would then informally be ##v = pc^2/0 = \infty##.
 
Orodruin said:
Tachyons have negative squared masses.

Why would you think that the speed should be 2c for a low energy tachyon? Generally, for any particle, ##v = pc^2/E##. All particles satisfy ##E^2 = (pc)^2 + (mc^2)^2## and so if the tachyon has negative mass squared, the energy of the tachyon can be zero. Its velocity would then informally be ##v = pc^2/0 = \infty##.

Okay. Thank you. Is there any possibility that a particle has an imaginary mass?
 
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