[Via Bad Astronomy]
The ‘Net has been buzzing about a paper published by a team of engineers at NASA claiming that they have built a device that creates thrust without propellant. There have been lots of articles written about it, it’s spawned a zillion tweets, and I’m getting plenty of email asking me about it.
Here’s the thing: I’m not convinced. I’m not saying it’s wrong, but I am saying it’s very, very likely to be some sort of measurement or experimental error.
I could write a lot about this, but instead I’ll point you to two people who already have written excellent discussions on what’s going on here: John Baez on Google Plus (you should read both his first article and his second one) as well as my old friend Steve Novella. Both dissect this report, and align pretty well with what I’m thinking. Update: After writing this post but before it went up, I found my friend Mika McKinnon also wrote a solid article about all this, too.
The bottom line here is what the team is proposing violates a very basic law of physics; all the forces inside the device appear to be balanced, yet a thrust is still generated. The law of conservation of momentum says that’s not possible. The only other way this device could possibly work is if it’s interacting with “virtual particles,” an interesting idea, but a highly speculative one—and the authors of the paper don’t discuss the physics. It’s important to note that the paper is not an official announcement of verified results; it’s more like a progress report.
I’ll be clear: Of course science has overturned earlier notions of how the Universe works. But sometimes, those rules are shown to be true so much and so often that when you come up with an idea that overthrows all of it, you’d better have iron-clad evidence of it.
All the NASA guys did was test something that others had stated produced an unknown force on the article. They found something but, as this article mentions, this does not ‘prove’ anything.
It simply shows something interesting. The answers could be very prosaic. Or they could revolutionaize the world.
That is what makes scoence great. Unfortunately, most of the time the answer is prosaic. So let’s just wait a bit. Before we start planning trips to Mars.