Since you own the only copy and nothing can force you to publish it, you can keep the original from going to the public for as long as you want.
This allows you to prepare a derivative work (such as an annotated version) to which you can attach your own copyright. Voila, you own the derivative, and the clock doesn't start until you are finished.
Your great grandfather was a famous writer. Your parents never did anything with the property where his house was, but when you inherited it, you went up there and found a first draft, never been published, masterpiece. But it has been far more than 20 years since he died and publishers refuse to publish it because it is already public domain.
No it isn't. IIRC, the term of copyright extends from first publication (think how long something might take to edit; the clock isn't running during that period, it starts on the date of publication). If that manuscript has been unpublished, it's still got the full term ahead of it (at least for the corporate term).
And if the wall has no power right now, or there is no wall? You're going to feel really silly there with a dying battery and your line-powered charger.
There are a lot of things your clothes do to absorb energy that you don't notice. You don't want the soles of your shoes to be too springy, for example. If you can put some of the absorbed energy to good use instead of turning it into heat, you'd never notice the difference.
If all the CDs are burning at once, you have to do one read and many writes. Speed of the hard disk is not a factor. Speed of the bus and drive interfaces might be.
If a CD holds 660 MB and holds 1 hour of audio, that's a data rate of 11 MB/minute. Burning at 24x, that's 264 MB/minute. Bandwidth of a 64-bit wide PCI bus at 66 MHz is 528 MB/second, some 120 times the requirement of the single CD drive. It would appear that one could burn 10 or 20 CDs at a time at 24x and have plenty of bus bandwidth left over (so long as you were burning in parallel).
I'm not qualified to judge the architectural features which might create other bottlenecks, but neither the hard drive nor the machine bus appear to be a difficulty.
I'm sure that the engineers who will eventually design a lithium, liquid metal wall reactor will have no idea what to do with all this spare fuel they are generating.
Or maybe they'll just put some boron in the system to soak up some neutrons via the B-11 + n -> 3 He-4 reaction. It's a lot easier and probably cheaper than trying to contain, inventory and dispose of a whole lot of unneeded tritium.
One of the first concepts for the use of lithium as a renewable "first wall" involved chambers which contained a vortex flow more or less like a toilet bowl. Pellets of D-T would be dropped into the center of the vortex and triggered with laser pulses; the flowing lithium would absorb the energy of the resulting micro-explosion and renew itself in time for the next pulse. The lithium would also carry away the heat. This concept was discarded when it was found that laser fusion required implosion of material to far higher densities than could be obtained with a single incoming beam, and the necessary symmetric system of incoming beams prohibited the use of a lithium vortex.
This concept appears to use lithium as the "first wall". I'm not sure exactly what the first wall has to absorb, besides the heat conducted to it from plasma leakage (plasmas do leak, they are subject to all kinds of instabilities) and soft X-rays. I do know that if you had a symmetric torus you could rotate the magnets to "pump" the liquid metal along the wall using eddy-currents, but I expect that this would be far more expensive and difficult than what they're planning. You can't have two different magnetic fields; you have one field, which is the sum of all the fields induced by all the current-carrying elements in the reactor, plus whatever the Earth decides to give you (which is probably not significant on this scale). You could have a multi-pole magnetic field at the surface which would fall off rapidly toward the center (not unlike the focussing magnets used in a synchrotron) but I'm not sure what effect this would have on either the metal wall or the plasma (and unlike synchrotrons, I don't know any tokamak experts I could ask).
Logically, a layperson would consider a liquid metal to be a very dangerous material to have around...
Like solder? It can burn you, you know. But so can a great many solid materials and vapors (even water). You do have the toxicity of lead-based solders, but they're toxic even when they're in solid form.
Lithium is gonna come in contact with water somehow, by accident (or design) and make hydrogen gas [gcsechemistry.co.uk] which is not only explosive, but turns into radioactive tritium when bombarded by the neutrons put out by ANY reactor - fission or fusion.
The lithium will breed tritium under neutron bombardment whether water is involved or not; the production of hydrogen is a chemical reaction caused by the decomposition of water, the production of tritium is a nuclear reaction caused by the neutron-induced fission of lithium-6 into helium-4 and hydrogen-3.
Lithium is a lot less active (and thus corrosive) than sodium, but it's not suitable as a coolant for fission reactors because it has this pesky tendency to capture neutrons. In a fusion reactor which needs tritium anyway, this is an advantage.
Playing around with explosive hydrogen gas near a reactor is often done deliberately and may be a hidden agenda here.
Just FYI, people play around with "explosive hydrogen gas" for lots of reasons in lots of places. You'll find people playing with hydrogen in every plant which manufactures vegetable shortening from oil, because hydrogenating the oil is part of the process to allow it to solidify at room temperature. Ditto every plant which manufactures nitrogen fertilizers (which starts with fixation via the Haber process, N2 + 3 H2 -> 2 NH3).
A little more information and a little less paranoia would serve you well.
and then direct a torrent of neutrons to collide head-on.
No fusion reactor does any such thing. Collisions of neutrons with neutrons do not figure in any reactor currently contemplated, fusion or fission; the only collisions are between neutrons and nuclei, or between nuclei themselves. So why is a science-illiterate writing an article about the cutting edge of fusion research, and why should we give the slightest bit of credence to either an author or a news outlet which would let something like this go out without proper fact-checking?
If you have any question about whether or not in-circuit reflashability is a good idea, look at the auto industry. Very soon, every part in the car that has a connection to the vehicle bus will be specced to receive software upgrades from the bus. And why not? Have you considered how expensive it is to pull a million modules from inside the dashes, beneath the seats or even from under two other things inside the engine compartment, re-flash them, and put them back?
The economics of your company are probably quite a bit different from the auto industry; your volume is probably several orders of magnitude less, to name one thing. But you have to consider the loss of goodwill if customers have to pull hardware and ship it to you for firmware fixes, instead of taking 20 minutes to download and install a new patch. You might also consider the benefits of being able to sell firmware functionality upgrades for units already installed; the customers will love you for teaching their old dog a new bunch of tricks.
You get a mixture of hydrogen and oxygen out of such a beast. You can separate them using well-understood techniques, such as allowing the hydrogen to diffuse through palladium leaving the oxygen behind. I seem to recall that there are cells which can use an H2/O2 mix directly, but I'd be leery about having very much of such a gas mix in any one place.
The idea which occurs to me about this is that a collector could perhaps be used to harvest part of the energy as H2/O2 and the remainder as heat. If you did this with distilled water and catalyst, and allowed the mix to heat up until you had low-pressure steam with "contaminants" (diluted with water vapor to below the flammability limit), you could harvest energy in two useful forms and make productive use of the waste heat from the catalytic decomposition process.
Electricity producing silicon solar-cells actually take more energy and generate more pollution during manufacture, than they will ever generate.
The figures I read say that the panels pay back their energy of construction in 2-4 years. Lifetime of a typical panel is at least 20 years, possibly upwards of 30 years.
The nice thing about conversion directly to hydrogen, is that it is definetly an easier way to concentrate the energy.
Conversion directly to hydrogen eliminates a bunch of intermediate steps. If you're making hydrogen from sunlight anyway, you might as well do it in the way which is simplest and cheapest.
I personally think that hydrogen isn't as easily transported as e.g. aluminum metal (you won't have any NOx emissions from aluminum-air batteries, and the fuel doesn't leak either), but the popular consciousness among the ecology-minded doesn't seem to be able to grasp conservation of energy, let alone economic payback and leveraging techniques.
How many of these technologies would be worthwhile for other purposes and could be developed for scientific or even profit-making purposes in the mean time?
(Of course, I'm asking this because nobody is going to devote such resources and focus on one far-off goal long enough to accomplish it; anyone who does will lose other competitions to groups which do not. On the other hand, if the goal can be accomplished via a number of short-term projects each of which is useful and even profitable in its own right, the grand goal follows almost inevitably.)
Being out in BFE means a far smaller likelihood of another star passing close enough to perturb the orbits of all the planets in a system. The impact of comets can change climate briefly, but with a huge effect on life; think what a semi-permanent (until the next perturbation) change in climate could do to life which had evolved for a particular set of conditions. A few trips through an over-greenhoused state would be enough to wipe out most everything but extremophile bacteria, making it very unlikely that higher life forms (let alone intelligence) could develop.
The fiber has to have "sides" so that there is only one mode - one solution to the wave equation - that the light can take through the fiber. It's like radio travelling over a coaxial cable; the energy isn't bouncing between the inner and outer conductors, or at least it can't until the circumference of the cable approaches a wavelength (which it can with big cables and really high microwave frequencies); then you get dispersion and other strange effects. Bending the fiber doesn't make anything "bounce", it just changes the boundary conditions and forces the wave to curve with the glass (and allows some probability of photons leaking out of the core if the curvature is tight enough, which is how some fiber-tapping techniques work).
You get delays due to the velocity factor of the cable; this is mostly due to the dielectric behavior of the insulation (which is unlrelated to friction).
You'd have the same delays in fiber; light travels more slowly though glass than through vacuum, in no small part because of the dieletric properties of glass. In case you're wondering, the speed of light in a medium is equal to 1/; when and are the values for vacuum, v = c.
(Yes, I'm a physics nut and I studied this crap for my degree. About the only thing I use it for is to set people straight about physics.)
I think you underestimate the power of self-interest. If people knew, from controlled studies (or as well-controlled as the methodology was up to at the time; it appears from what little I've seen that the controls on this one were pretty good even by modern standards) that keeping a diverse species mix led to more fodder and crop production, we would have jump-started a whole bunch of movements which are just now getting their momentum in modern agriculture.
There is no better way to make someone take notice of an advance in knowledge than showing them how to make a buck off it. (Well, maybe. Show them how to use it to win against their enemies. But arguably that's the same result, different game.)
In case you hadn't noticed, your analysis assumes the use of chemical fuels in a conventional rocket. I can think of two technologies which could easily violate those assumptions:
Laser-detonated "ice rocket", and
Lofstrom loop.
In the case of the Lofstrom loop, the efficiency of conversion of electricity to kinetic energy of the object to be placed in orbit might be over 50%. The total energy required is mgh + 0.5mv, or 800000*9.8 + 0.5*7600 = 36.72 MJ/kg. Call it 10 KWH/kg; at $.10/KWH and 50% efficiency, the energy cost would be $2/kg.
Exploring technologies like these would break enough of the current assumptions behind the conclusion of "it can't be done" to really make a difference.
I'd like to see your figures showing that 1000 times Earth's current population could live here easily. We are already having serious shortages of essentials like fresh water; care to describe how that problem can be eliminated, or is your analysis one which leaves that exercise for the student?
You seem to have the impression that Congress would approve a large budget for a profit-making project which NASA would then use to become independent (financially, anyway) of Congress. Did you really think that Congress would do this and let NASA keep the money? Hint, the fees paid to the USPTO and other agencies does not finance the agencies, it goes into the general fund at the US Treasury; some of these agencies more than pay for themselves, but they have to beg Congress for money for essentials.
You also have a touching belief in the purity of spirit of politicians. Hopelessly naive, but touching.
NASA gets money based on how successfully it lobbies Congress. NASA has a much easier time when it has other people's lobbyists, such as those from the aerospace industry, lobbying alongside them; if NASA can't get money for a project, it can't do the project.
If we could somehow break the constituencies for boondoggles like the ISS and break the dams holding back money for things like the DC-1 and Mars Direct, we could get somewhere. It could happen if there was a groundswell of public interest which out-shouted the lobbyists for the current pork-barrel schemes. Unfortunately, the public really doesn't care much for space, and unless enough people's votes can be changed by a pol's position on the issue, the pols are not going to change the way the money is flowing.
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This allows you to prepare a derivative work (such as an annotated version) to which you can attach your own copyright. Voila, you own the derivative, and the clock doesn't start until you are finished.
Disclaimer: IANAIPL.
And if the wall has no power right now, or there is no wall? You're going to feel really silly there with a dying battery and your line-powered charger.
There are a lot of things your clothes do to absorb energy that you don't notice. You don't want the soles of your shoes to be too springy, for example. If you can put some of the absorbed energy to good use instead of turning it into heat, you'd never notice the difference.
I thought of that a few years ago. It should be enough to power a thrifty laptop, too.
If a CD holds 660 MB and holds 1 hour of audio, that's a data rate of 11 MB/minute. Burning at 24x, that's 264 MB/minute. Bandwidth of a 64-bit wide PCI bus at 66 MHz is 528 MB/second, some 120 times the requirement of the single CD drive. It would appear that one could burn 10 or 20 CDs at a time at 24x and have plenty of bus bandwidth left over (so long as you were burning in parallel).
I'm not qualified to judge the architectural features which might create other bottlenecks, but neither the hard drive nor the machine bus appear to be a difficulty.
This concept appears to use lithium as the "first wall". I'm not sure exactly what the first wall has to absorb, besides the heat conducted to it from plasma leakage (plasmas do leak, they are subject to all kinds of instabilities) and soft X-rays. I do know that if you had a symmetric torus you could rotate the magnets to "pump" the liquid metal along the wall using eddy-currents, but I expect that this would be far more expensive and difficult than what they're planning. You can't have two different magnetic fields; you have one field, which is the sum of all the fields induced by all the current-carrying elements in the reactor, plus whatever the Earth decides to give you (which is probably not significant on this scale). You could have a multi-pole magnetic field at the surface which would fall off rapidly toward the center (not unlike the focussing magnets used in a synchrotron) but I'm not sure what effect this would have on either the metal wall or the plasma (and unlike synchrotrons, I don't know any tokamak experts I could ask).
Lithium is a lot less active (and thus corrosive) than sodium, but it's not suitable as a coolant for fission reactors because it has this pesky tendency to capture neutrons. In a fusion reactor which needs tritium anyway, this is an advantage.
Just FYI, people play around with "explosive hydrogen gas" for lots of reasons in lots of places. You'll find people playing with hydrogen in every plant which manufactures vegetable shortening from oil, because hydrogenating the oil is part of the process to allow it to solidify at room temperature. Ditto every plant which manufactures nitrogen fertilizers (which starts with fixation via the Haber process, N2 + 3 H2 -> 2 NH3).A little more information and a little less paranoia would serve you well.
The economics of your company are probably quite a bit different from the auto industry; your volume is probably several orders of magnitude less, to name one thing. But you have to consider the loss of goodwill if customers have to pull hardware and ship it to you for firmware fixes, instead of taking 20 minutes to download and install a new patch. You might also consider the benefits of being able to sell firmware functionality upgrades for units already installed; the customers will love you for teaching their old dog a new bunch of tricks.
The idea which occurs to me about this is that a collector could perhaps be used to harvest part of the energy as H2/O2 and the remainder as heat. If you did this with distilled water and catalyst, and allowed the mix to heat up until you had low-pressure steam with "contaminants" (diluted with water vapor to below the flammability limit), you could harvest energy in two useful forms and make productive use of the waste heat from the catalytic decomposition process.
I personally think that hydrogen isn't as easily transported as e.g. aluminum metal (you won't have any NOx emissions from aluminum-air batteries, and the fuel doesn't leak either), but the popular consciousness among the ecology-minded doesn't seem to be able to grasp conservation of energy, let alone economic payback and leveraging techniques.
(Of course, I'm asking this because nobody is going to devote such resources and focus on one far-off goal long enough to accomplish it; anyone who does will lose other competitions to groups which do not. On the other hand, if the goal can be accomplished via a number of short-term projects each of which is useful and even profitable in its own right, the grand goal follows almost inevitably.)
Being out in BFE means a far smaller likelihood of another star passing close enough to perturb the orbits of all the planets in a system. The impact of comets can change climate briefly, but with a huge effect on life; think what a semi-permanent (until the next perturbation) change in climate could do to life which had evolved for a particular set of conditions. A few trips through an over-greenhoused state would be enough to wipe out most everything but extremophile bacteria, making it very unlikely that higher life forms (let alone intelligence) could develop.
What will it take to get a program going to actually send people out to them?
The fiber has to have "sides" so that there is only one mode - one solution to the wave equation - that the light can take through the fiber. It's like radio travelling over a coaxial cable; the energy isn't bouncing between the inner and outer conductors, or at least it can't until the circumference of the cable approaches a wavelength (which it can with big cables and really high microwave frequencies); then you get dispersion and other strange effects. Bending the fiber doesn't make anything "bounce", it just changes the boundary conditions and forces the wave to curve with the glass (and allows some probability of photons leaking out of the core if the curvature is tight enough, which is how some fiber-tapping techniques work).
Light does not "bounce" through single-mode fibers, and that category covers most long-distance transmission fiber.
Make that sqrt(1/). In my hurry to post I made an error (and a bunch of people got their two cents in first).
You'd have the same delays in fiber; light travels more slowly though glass than through vacuum, in no small part because of the dieletric properties of glass. In case you're wondering, the speed of light in a medium is equal to 1/; when and are the values for vacuum, v = c.
(Yes, I'm a physics nut and I studied this crap for my degree. About the only thing I use it for is to set people straight about physics.)
There is no better way to make someone take notice of an advance in knowledge than showing them how to make a buck off it. (Well, maybe. Show them how to use it to win against their enemies. But arguably that's the same result, different game.)
- Laser-detonated "ice rocket", and
- Lofstrom loop.
In the case of the Lofstrom loop, the efficiency of conversion of electricity to kinetic energy of the object to be placed in orbit might be over 50%. The total energy required is mgh + 0.5mv, or 800000*9.8 + 0.5*7600 = 36.72 MJ/kg. Call it 10 KWH/kg; at $.10/KWH and 50% efficiency, the energy cost would be $2/kg.Exploring technologies like these would break enough of the current assumptions behind the conclusion of "it can't be done" to really make a difference.
I'd like to see your figures showing that 1000 times Earth's current population could live here easily. We are already having serious shortages of essentials like fresh water; care to describe how that problem can be eliminated, or is your analysis one which leaves that exercise for the student?
You also have a touching belief in the purity of spirit of politicians. Hopelessly naive, but touching.
If we could somehow break the constituencies for boondoggles like the ISS and break the dams holding back money for things like the DC-1 and Mars Direct, we could get somewhere. It could happen if there was a groundswell of public interest which out-shouted the lobbyists for the current pork-barrel schemes. Unfortunately, the public really doesn't care much for space, and unless enough people's votes can be changed by a pol's position on the issue, the pols are not going to change the way the money is flowing.