You are here:

Astrophysics/Alcubierre drive question


If we assume that FTL with Alcubierre drive is possible, could you going by that assumption find any reason why an Alcubierre drive would have a top speed it can reach like for instance 4380 times the speed of light?

Hi Mika,

The limit, as I see it, would be determined from the rate at which (negative) energy must be extracted from the vacuum or the total amount of exotic (negative mass) material available. Conservation of energy (positive or negative) would still seem to apply. Unless there's a spontaneous symmetry breaking - in that case, I can't see a limit. Which doesn't mean there isn't one. It just means we're dealing with a largely unknown region of GR (or quantum gravity). Or something else.

Prof. James Gort  


All Answers

Answers by Expert:

Ask Experts


James Gort


Questions on observational astronomy, optics, and astrophysics. Specializing in the evolution of stars, variable stars, supernovae, neuton stars/pulsars, black holes, quasars, and cosmology.


I was a professional astronomer (University of Texas, McDonald Observatory), lecturer at the Adler Planetarium, professor of astrophysics, and amateur astronomer for 42 years. I have made numerous telescopes, and I am currently building one of the largest private observatories in Canada.

StarDate, University of Texas, numerous Journal Publications

B.A. Physics and Astronomy M.Sc. Physics Ph.D. Astrophysics

©2017 All rights reserved.