The Time Machine Factory [unspeakable, speakable] on Time Travel - TMF2024

Relativistic tunneling and attempts at superluminal signaling

25 Sept 2024, 09:00

25m

Vallauri Hall (INRiM historical building, Turin)

talk Session V. Teleportation, entanglement and decoherence

Speaker

Randy Dumont (McMaster University)

Description

Numerical solutions of the Dirac equation show that, post-selected for tunneling, relativistic electrons can exhibit transit time distributions with a peak corresponding to superluminal effective velocity. However, a non-negligible effect is seen only when tunneling probability is very small. If one attempts to send a signal using many electrons to compensate for the low tunneling probability, a distribution of signaling times is obtained with superluminal effective speed. However, we find that the signal always arrives slightly earlier if carried by the same number of photons traveling in a vacuum. The effective superluminality that is seen results from the uncertainty in the initial particle - electron or photon - position.

Presentation materials

Dumont_DiracT_Torino_24.pdf