I asked about a plausible physical phenomenon - something that can be seen and measured in the real world. You will never measure a passable E-R bridge or Alcub

I asked about a plausible physical phenomenon - something that can be seen and measured in the real world. You will never measure a passable E-R bridge or Alcubierre drive because it's purely mathematical exercise, it has zero possibility/probability of being engineered into existence as it relies on things that straight-up can never exist. I'm not saying FTL is impossible but it's definitely not going to be either of these - our universe would be totally broken and self-destruct if these were possible.