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Posted: Sun Nov 18, 2012 5:10 am
by GIThruster
I think people are jumping the gun here somewhat. I haven't read the paper, but the ability for particles to enter the warp bubble is highly suspect.

Likewise, the thesis that incoming interplanetary craft could be used like jet airliners is highly suspect. After all, there's no reason to build hypersonic reentry ability into a craft that can levitate and enter the Earth's atmosphere at very low speed. Hypersonics are difficult and unnecessary for anything other than military craft. Civilian craft would reflect the same common sense design that has stopped us from having supersonic transports over the continents. Just isn't necessary. Without a hypersonic reentry ability, any normal ship would burn up well before it ever got close to Earth. There'd be a flash and maybe some EMP but certainly it wouldn't be landing like a bomb.

And as I've noted before, it's far easier to steal a freighter, fill it with fertilizer and blow up a city from port. Yet we don't panic over that possibility as well as hundreds of other doomsday scenarios. Rather, we just take the appropriate actions to see that doesn't happen.

Posted: Sun Nov 18, 2012 5:12 am
by zapkitty
williatw wrote:
zapkitty wrote:... velocity relative to what?
Your velocity relative to your destination is what you would be concerned about.
You misunderstand me, sorry :)

I meant why should a warp drive care about your velocity relative to anything before being engaged?

Curious... does this "boost" involve some variant of a preferred frame?

Posted: Sun Nov 18, 2012 7:09 am
by GIThruster
IIRC, this question also came up when Paul first espoused it here, and he corrected the issue by claiming the warp was in the direction of an initial acceleration, not a velocity.

Posted: Sun Nov 18, 2012 8:26 am
by cuddihy
GIThruster wrote: ~
And as I've noted before, it's far easier to steal a freighter, fill it with fertilizer and blow up a city from port. Yet we don't panic over that possibility as well as hundreds of other doomsday scenarios. Rather, we just take the appropriate actions to see that doesn't happen.
This just plain isn't true. A freighter full of fertilizer is a multi-decamillion asset. A bad actor owning one or filling one up gets noticed. It'd be cheaper to steal a Pakistani nuke.

Posted: Sun Nov 18, 2012 6:30 pm
by kurt9
Given that we don't know the results of White's and March's experiments, I would say that talk about warp effects is premature. However, the Mach effect itself, as demonstrated by Woodward, appears to be real. This suggests we really will get an SF-style space drive, but that it will be strictly a sub-light propulsion technology. Even this advance will make the entire O'niell space colony scenario doable and cost effective. It will open the solar system to human settlement. Mach effect technology will revolutionize conventional transportation as well, which is where the big money is for now.

Posted: Thu Nov 29, 2012 3:33 pm
by pbelter
An article in the Atlantic about Sonny's work.


http://www.theatlantic.com/technology/a ... ve/265655/

Nothing new but interesting they picked up on it. No mention of Woodward.

Posted: Fri Nov 30, 2012 12:12 am
by GIThruster
The io9 piece its taken from is better.

I certainly hope Sonny will publish his warp calculations soon. The longer he waits and the more he popularizes his model without the proper protocols, the more embarrassing it will be if he's made a math error. It is really not appropriate for him to be fundraising with fantasies instead of publishing.

The Warp interferometer could easily work and his Alcubierre mods still be wrong. Likewise his QV model could be completely wrong and he could get a warp field for other reasons. This is why he needs to start publishing--so others can look at his work.

Posted: Fri Nov 30, 2012 9:03 am
by GeeGee
Yes, it's rather concerning that Sonny has not attempted to get his calculation published in a decent journal. GR calculations are really tricky, so the probability of being wrong is not insignificant.

Posted: Mon Dec 03, 2012 5:26 am
by paulmarch
GeeGee wrote:Yes, it's rather concerning that Sonny has not attempted to get his calculation published in a decent journal. GR calculations are really tricky, so the probability of being wrong is not insignificant.
All:

Try this one at General Relativity and Gravitation (GERG) for starters:

"A Discussion of Space-Time Metric Engineering"

http://link.springer.com/article/10.102 ... 18?LI=true#

Best,

Paul March

Posted: Mon Dec 03, 2012 8:46 am
by GeeGee
Paul,

I think you've shared that paper before. It's interesting stuff, but I was talking about the newest calculation of reduced energy requirements for a warp drive. A theoretical breakthrough like that needs peer-review.

Posted: Tue Dec 04, 2012 1:49 am
by djolds1
GeeGee wrote:Paul,

I think you've shared that paper before. It's interesting stuff, but I was talking about the newest calculation of reduced energy requirements for a warp drive. A theoretical breakthrough like that needs peer-review.
Agreed. A decade-old paper doesn't really address the most recent changes in perspective.

Posted: Sat Dec 08, 2012 7:45 am
by GeeGee
Dr. Fuerst is back, trashing Woodward

http://forum.nasaspaceflight.com/index. ... 13020.1770

Posted: Sat Dec 08, 2012 6:31 pm
by GIThruster
Fuerst seems to have a pattern of making his criticisms in forums where there is no one suited to contradict him. He had plenty of opportunity to make these kinds of statements to Jim in his private email list and didn't. I suspect his contention that vector analysis is not enough fails since it has not been offered through the proper peer review channels from the start.

I can say I don't appreciate Fuerst's cheezy rhetorical style with asking "so why don't other physicists use a vector theory of gravity?" In fact they do. Dennis Sciama's work on gravitation is all in vector. Physicists routinely use it because it's much simpler than tensor.

And in fact, Woodward never comes to the conclusion that momentum is not conserved. That's pure misrepresentation on the part of Fuerst.

Note too, Sonny White's explanation of thrust from the Shawyer resonator likewise does not break conservation, so that is two subjects Fuerst is writing on that he is not familiar with. And this is why we're no longer in touch. All of my conversations with him he was busy boasting, but he wasn't actually familiar with the topics he was boasting about. Discussion with him proved a waste of time.

Posted: Sat Dec 08, 2012 10:46 pm
by kurt9
I don't follow the criticism on the Nasa Starflight blog or anywhere else. Woodward has done a rigorous set of experiments that he has documented in his email list that demonstrate a real effect. The issue is whether the effect can be scaled, which is not certain as of yet. Either Woodward will prevail or he will not. This is the acid test of his ideas.

Posted: Sun Dec 09, 2012 12:17 am
by GeeGee
Fuerst is arguing a straw man from what I can tell. He insists that the M-E conjecture relies on a vector theory of gravity, but that's incorrect. Here's something I found in my e-mail a while back relating exactly to this issue

"I am not claiming (nor have I claimed) that Sciama's 1953 theory is exactly correct. What I do claim is that the formalism is the vector approximation to GR -- especially the dA/dt term in the gravelectric field equation. The same term, in the interpretation of this effect, shows up in the PPN version as Nordtvedt shows later as "linear accelerative frame dragging". And when the rigidly accelerating body producing the frame dragging is the observable universe, rigid frame dragging results (and, up to a constant factor of order unity, phi = c^2). The point is that whether you treat this as frame dragging or inertial force, the distant matter in the universe affects the inertial behavior of local objects by producing the reaction force when local objects are forced out of geodesic motion."

So no, Sciama's model isn't necessary for the M-E to exist. The same result is found in vanilla GR.

http://physics.fullerton.edu/~jimw/gene ... a/nord.htm