How Feasible Will It Be To Embark On Space Travel Using An Alcubierre Warp Drive

Casey Handmer

Unfortunately, coverage of that NASA press release has been along the lines of book your tickets now, rockets are going to obsolete by next year. This is not the case.

Harold White has built an interferometer to try and measure a warp bubble. How he intends to create this warp bubble has never been explained. I had a decent look at the paper he published. Light on details, unfortunately a decent chunk of it is consumed with speculation on how provisions and life-support might work on a warp-driven spacecraft. Like the linked articles "stunned the world", this is a damn good clue that this concept falls somewhere between hype and total bullshit.

The Alcubierre warp is an interesting solution of the Einstein Field Equation that describes how a warp drive could work. Unfortunately, no version of it has yet been found that satisfies the average null energy condition, which is the least stringent expression of the condition that physical solutions should not have closed time-like curves.

We have strong reasons to suppose the universe should not have closed time-like curves, like various paradoxes and other arguments. That said, weve been surprised before. Maybe they can exist, at least locally.

Lets say, for the sake of argument, that an Alcubierre-class solution is found which satisfies the relevant null-energy condition. I personally think that this could happen in our lifetime, especially if we get some unexpected physics from gravitational wave astronomy. Even then, however, we would still have no way of making a warp bubble, let alone controlling one. Its not just a matter of building a really big shiny spaceship and having lots of scientists in white coats running around. You need negative density matter or energy to create the bubble wall. No-one has any idea how to make or control that, or if it even exists. In fact, the only reason people think it might exist, at least at very large scales, is the expansion of the universe. But since no-one has really got any clue as to what dark energy is (though were getting closer on dark matter), this is likely to remain a problem for a very long time.

Incidentally, if you have negative energy matter and negative pressure energy (which I sometimes refer to as unicorns and pixie dust, to give an idea of how unlikely they are), you can make worm holes and keep them open and stable as matter passes through.

In summary, NASA is not building warp drive. Noone can build warp drive. Noone and nothing can be transported by warp drive. If you want to get into space, youre going to need rockets. If you want to go even to the nearest stars, youre going to need fusion or antimatter and decades of your life.

See question on Quora