[parley]

I seem to remember Elon Musk getting a question about SABRE at a post-talk Q&A a while back (probably in the UK, perhaps an inauguration ceremony of some institution), but now I can't find it. He was skeptical and had some constructive things to say, but I'm not a physicist so unfortunately I can't remember the specifics. If anyone else finds it, kindly reply with a link!

EDIT: Found the video, but haven't yet found the specific time of the question. My connection is a bit slow, so jumping around in the stream isn't going so well. http://www.oxfordmartin.ox.ac.uk/videos/view/211

EDIT 2: Found it. Elon's reply is at 48:55.

[arethuza]

Maybe he doesn't like it because it won't work on Mars? :-)