Do tachyons violate EPR?

Are they responsible for super-luminal communication (and possibly entangled states with greater than space like separation)?

What are the current perspectives on the subject?

 

Please express your opinion.

 

Thanks in advance.

Tachyons have not been demonstrated to exist.

The current thinking is that (standard) tachyons are inherently unstable and will decay rather quickly. Quantum mechanically they will not propagate at speeds faster than light, but rather decay into stable particles. This is related to the idea of tachyon condensation.

The current thinking is that (standard) tachyons are inherently unstable and will decay rather quickly. Quantum mechanically they will not propagate at speeds faster than light, but rather decay into stable particles. This is related to the idea of tachyon condensation.

 

Does the current thinking put tachyons outside the light cone and do they have zero rest mass (which seems unlikely) since they decay?

Are they categorized as bosons or fermions?

Please provide some insight.

Your thoughts will be appreciated.

Does the current thinking put tachyons outside the light cone and do they have zero rest mass (which seems unlikely) since they decay?

Standard tachyons have negative mass squared.

 

Are they categorized as bosons or fermions?

Tachyons are scalar bosons if we make a few natural assumptions

Are they responsible for super-luminal communication (and possibly entangled states with greater than space like separation)?

Simultaneous choice by distant entangled particles does not permit to transmit information. Present formulations of entanglement do not seek a physical means to relate the choice by the particle pair.

 

Superluminal communication would ruin Relativity, since the finite speed of information is its fundamental hypothesis - not a remote consequence of increasing mass or speed addition.

 

As such, tachyons allowing to transmit information would be a serious headache to present physics... But they were - at the time they made the buzz - nothing more than an exotic math solution needed by no observation.

 

By the way, what would the group speed of tachyons be? Are they a usual question of phase versus group speed?