As I mentioned last week, I have relocated to Cleveland. Furniture and books (the important things) are still en route, with a scheduled arrival on Thursday. In the meantime, between waiting for various technicians to show up and wandering my new neighborhood, I decided to reduce the amount of writing I do temporarily, in hopes of getting a little rest and clearing my head.
However, I did manage to squeeze one piece out, published in The Daily Beast yesterday in lieu of my usual weekly column. The article is a response to a number of reports about a new type of thruster being tested at a semi-independent NASA lab. The thruster is … a bit questionable in its design principles and theoretical justification.
However, it’s also fair to ask whether the thruster works, regardless of whether the explanation is correct. Even there, the answer is no, as physicist John Baez explains in detail. The TL;DR version: the NASA researchers didn’t test the thruster in a vacuum, which means they can’t rule out the possibility of disturbances by air currents. They also found the same results when they tested their “control” apparatus, designed to give zero thrust, which means basically their experiment failed—yet they still reported it as a success. Additionally, the amount of force the researchers measured is quite small compared with the input energy, meaning it’s probably explainable using more mundane physics: no exotic quantum effects needed. [Read more…]
I confess, though, that I’m dissatisfied with the article as it turned out. I’m not exactly sure what to do differently (and since it’s published, there’s no real going back), so I won’t attempt a full postmortem here. However, I recommend reading these other pieces to get a full picture of what’s going on and what’s (probably) not happening.
- Two by John Baez: The incredible shrinking force and a follow-up with details about the “quantum vacuum plasma thruster”
- Chad Orzel delved into what would be required to test this drive concept properly, and why the current tests didn’t cut it
- Phil Plait hedged his bets a little more than the rest of us, but still came down heavily on the side of skepticism
I’m sure there are many more essays, rants, and articles on this topic, since it’s the kind of thing that grabs a physicist’s attention, if only to give her a headache.