FUENTE: Sabine Hossenfelder
21 de noviembre de 2020

What is a warp drive? Are they scientifically possible? How does the Alcubierre drive work? That’s what we talk about today.

When I talk about energy conservation around 7 mins, I am NOT referring to the conservation of the stress-energy-tensor. This is conservation is always fulfilled if Einstein’s field equations are fulfilled by way of the (contracted) Bianchi identities. I am talking about the conservation of the four-momentum (the integrated quantity) that is associated with the warp-drive bubble. In an asymptotically flat space-time, it should be conserved. If the bubble accelerates, it isn’t. (As you’d expect.)