Spaceship Design

If polywell fusion is developed, in what ways will the world change for better or worse? Discuss.

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Mikos
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Joined: Wed Jan 16, 2008 3:19 pm
Location: Prague, Czech Republic

Post by Mikos »

Zixinus wrote:Somehow that doesn't make sense to make. Personally, it sounds like technobabble, or at least something that might not work effectively in the vacuum of space. I know they can use laser cooling to make Borns-Einstein Condensatum (spelling?) but that is done by getting rid of the "hottest" molecules (so that cool heads would prevail :P). Essentially, active cooling done on a atomic scale. The atoms are held by lasers.
This has nothing to do with laser cooling (as used e.g. for creation of Bose-Einstein condensate). It was simply radiating heat away from ship by gas dynamic laser principle. So you have one really bright point (laser) instead of large radiators.

But of course you can be right that it is wrong idea, but if I remember it right, thermodynamical concerns were addressed in that paper. The rule is that overall entropy must be increased and according to that paper, it is possible with gas dynamic laser concept (and enough energy). But without that paper, these are meaningless speculations, unfortunately I don't remember much from it :-(

Or is there somebody who can say if it is good or wrong idea? Somebody who knows gas dynamic lasers well? Can it be done that way that there would be no violation of thermodynamics laws?
"Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety."
-- Benjamin Franklin

TallDave
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Joined: Wed Jul 25, 2007 7:12 pm
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Post by TallDave »

Wow, Heim theory! I haven't seen that mentioned in a long time.

I think I remember reading that supposedly someone was going to try to test it. I'll have to dig around and see if anyone found anything worthwhile. A long shot, of course.

Last time I saw it discussed was the aftermath of an ESA experiment that created artificial gravity many orders of magnitude greater than relativity says should have been produced. It was mentioned as a thereotical framework that might account for it.

http://www.deanesmay.com/posts/1143235878.shtml

http://en.wikipedia.org/wiki/Artificial ... omagnetism

http://en.wikipedia.org/wiki/Heim_theor ... vity_force

Heim's predictions for a quantum gravity force
In the 1950s, Heim had predicted what he termed a 'contrabary' effect whereby photons, under the influence of a strong magnetic field in a certain configuration, could be transformed into 'gravito-photons', which would provide an artificial gravity force. This idea caused great interest at the time [15]. A recent series of experiments by Martin Tajmar et al., partly funded by ESA, may have produced the first evidence of artificial gravity [16] (about 23 orders of magnitude greater than what General Relativity predicts). As of late 2006, groups at Berkeley and elsewhere were attempting to reproduce this effect. By applying their 'gravito-photon' theory to bosons, Droscher and Hauser were able to predict the size and direction of the effect [14]. A further prediction of Heim-Droscher theory shows how a different arrangement of the experiment by Tajmar et al. could produce a vertical force against the direction of the Earth's gravity. However, in July 2007, a group in Canterbury, New Zealand, said that they failed to reproduce Tajmar et al's effect, concluding that, based on the accuracy of the experiment, any such effect, if it exists, must be 21 times smaller than that predicted by the theory proposed by Tajmar in 2006.[15] Tajmar et al., however, interpreted a trend in the Canterbury data of the order expected, though almost hidden by noise. They also reported on their own improved laser gyro measurements of the effect, but this time found 'parity breaking' in that only for clockwise spin did they note an effect, whilst for the Canterbury group there was only an anti-clockwise effect [16]. In the same paper, the Heim-Theory explanation of the effect is, for the first time, cited as a possible cause of the artificial gravity.
More testing needed, I guess. I briefly corresponded with Tajmar at the time; I'll have to ask if anything new is forthcoming.

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