from Hacker News

Some Emerging Possibilities For Space Propulsion

by mike_esspe on 6/10/14, 12:57 PM with 58 comments

  • by Steuard on 6/10/14, 1:26 PM

    Speaking as a professional physicist, this page feels awfully light on actual information. And as far as I can tell, that's merited: there's not a lot of solid science discussed on this page, or even especially tantalizing ideas for what might come next.

    They spend a lot of time discussing quantum vacuum energy, but the one short note about its "propulsion implications" includes the comment that "Those particular gravity theories are still up for debate." That's perhaps generous: quantum gravity isn't far from my field, and I've never heard of this take on the origin of gravity and inertia.

    I'm also rather puzzled by the quote "Although gravity’s effects on electromagnetism and spacetime have been observed, the reverse possibility, of using electromagnetism to affect gravity, inertia, or spacetime is unknown." That's really not at all true. Our models of gravity all include very well-defined effects of electromagnetism on spacetime: the energy density in those fields causes space to curve, just like any other form of mass or energy. Hypothesizing anything else would require fundamental changes to the theory. That's entirely possible! But it's misleading to characterize the current state of affairs as having an unfilled gap like this.

    So yeah. I'd love a good spacedrive as much as the next guy. But this article doesn't do much to make me optimistic about it.

  • by sehugg on 6/10/14, 2:08 PM

    For something a bit more realistic, we are still studying nuclear propulsion in fits and starts since we halted its development in the 60s:

    http://www.nasa.gov/topics/technology/features/ntrees.html#....

  • by madaxe_again on 6/10/14, 4:10 PM

    Here's an interesting Wired interview with Podkletnov on his anti-gravity work from '97 : http://archive.wired.com/wired/archive/6.03/antigravity.html...
  • by eudox on 6/10/14, 1:54 PM

    I honestly can't imagine why NASA even acknowledges the idea of FTL travel - Is there some kind of propeller beanie PAC forcing their hand?

    They should just have a page that says: "FTL is impossible, but that's fine, once you get used to the way things are."

  • by thearn4 on 6/10/14, 1:18 PM

    NASA used to have a small program to evaluate concepts for breakthrough propulsion, which ended around 2002.

    http://www.grc.nasa.gov/WWW/bpp/

  • by jcfrei on 6/10/14, 5:53 PM

    I would be much more excited if NASA resumed the research on NERVA (http://en.wikipedia.org/wiki/NERVA). 50 years later a nuclear propulsion drive still seems like the most promising and cost-efficient way to explore our solar system.
  • by sdegutis on 6/10/14, 2:03 PM

    "Theory for a faster-than-light "warp drive" consistent with general relativity."

    For real?

  • by misterfusion on 6/10/14, 11:16 PM

    A real-life warp drive can be practically possible by employing phased standing waves. http://www.youtube.com/watch?v=6zh9abFF3ZE
  • by throwwit on 6/11/14, 1:06 AM

    The submitter should have tacked on (2007).