From the 'review': 'What follows is not a comprehensive examination of the information contained in the text (which would require more text than EE itself), but rather a summary of the history and politics that make the book significant, and my own perspective as a biologist on how that context produced a text that's wildly inappropriate for use in a science classroom.'
Why do you say 'a review shows it to be chock full of bad science and questionable reasoning', in light of the above admission that the reviewer isn't even actually reviewing the book?
I tried to find a link here which would dice the EE book into little pieces but, I could not find one. The only review linked appears to trash the teaching methodology, not the content. Where can I find a review of the scientific content, or lack thereof?
If so, obviously not for the reasons given by Roger Shawyer. But, what if we could generate an enormous amount of stored electromagnetic energy that was somehow asymetrically distributed? How would it affect local gravity? We know that the Reissner-Nordstrom solution of Einstein's General Theory creates a "repulsive" curvature which at some point cancels out the gravitational curvature, then dwindles rapidly with distance. Einstein's curvature equations haven't been and probably can't be solved in closed form for this problem. Does anyone out there know if there are numerical solutions which show what might be the curvature surrounding a resonating cavity?
You most certainly can excite an upper mode from the ground. All you have to do is hit it with the right frequency. Not only that, but that is not the only place you will get excitation. You've got thermal expansion and contraction going on all the way up. You've got tidal forces. You start moving around a good bit and you'll start to get Coriolis acceleration pumping your modes.
You do not want to fire thrusters to damp out oscillation. They would have to be placed all along the elevator, at least four thursters at each location (at least two locations per critical node) for 3-axis control, with all the additional weight that entails and a hazardous network for replenishing highly reactive propellants. Not only that but, damping vibrations with thrusters is extremely risky as you are quite likely to pump energy in rather than take it out. No, what would be needed would be a network of passive dampers such as they use in skyscrapers in Japan to damp out earthquakes. We are talking a lot of added weight here.
You need to be a little careful criticizing others for "ignorance". You appear to live in a glass house.
Yes, not only can you excite any mode but, energy dissipation is likely to be exceedingly low, meaning that oscillations can grow almost without bound even with a very small excitation. This is a significant problem but, one that has generally been off the radar screen for space elevator enthusiasts.
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From the 'review': 'What follows is not a comprehensive examination of the information contained in the text (which would require more text than EE itself), but rather a summary of the history and politics that make the book significant, and my own perspective as a biologist on how that context produced a text that's wildly inappropriate for use in a science classroom.' Why do you say 'a review shows it to be chock full of bad science and questionable reasoning', in light of the above admission that the reviewer isn't even actually reviewing the book?
I tried to find a link here which would dice the EE book into little pieces but, I could not find one. The only review linked appears to trash the teaching methodology, not the content. Where can I find a review of the scientific content, or lack thereof?
If so, obviously not for the reasons given by Roger Shawyer. But, what if we could generate an enormous amount of stored electromagnetic energy that was somehow asymetrically distributed? How would it affect local gravity? We know that the Reissner-Nordstrom solution of Einstein's General Theory creates a "repulsive" curvature which at some point cancels out the gravitational curvature, then dwindles rapidly with distance. Einstein's curvature equations haven't been and probably can't be solved in closed form for this problem. Does anyone out there know if there are numerical solutions which show what might be the curvature surrounding a resonating cavity?
You most certainly can excite an upper mode from the ground. All you have to do is hit it with the right frequency. Not only that, but that is not the only place you will get excitation. You've got thermal expansion and contraction going on all the way up. You've got tidal forces. You start moving around a good bit and you'll start to get Coriolis acceleration pumping your modes. You do not want to fire thrusters to damp out oscillation. They would have to be placed all along the elevator, at least four thursters at each location (at least two locations per critical node) for 3-axis control, with all the additional weight that entails and a hazardous network for replenishing highly reactive propellants. Not only that but, damping vibrations with thrusters is extremely risky as you are quite likely to pump energy in rather than take it out. No, what would be needed would be a network of passive dampers such as they use in skyscrapers in Japan to damp out earthquakes. We are talking a lot of added weight here. You need to be a little careful criticizing others for "ignorance". You appear to live in a glass house.
Yes, not only can you excite any mode but, energy dissipation is likely to be exceedingly low, meaning that oscillations can grow almost without bound even with a very small excitation. This is a significant problem but, one that has generally been off the radar screen for space elevator enthusiasts.