...keep in mind that it's the outlandish ideas that make the slightly crazy ideas look plausible, thus enabling the ultimate acceptance of radical thought processes. Necessary, yes?
The image below is a Dyson Swarm, an original concept by English-American Freeman Dyson. He's a futurist that opposes nuclear armament...that's a vision I'm more than happy to embrace.
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The Swarm is undoubtedly the most plausible of Dyson's Sphere concepts. In Sphere theory, a star is completely encompassed with individual satellites and/or biospheres in order to harness all of the power and energy emitted from that star. In the aforementioned picture, the concept is the same as his sphere concept (described below) but on a much smaller in scale. In this case, numerous satellites or biospheres will share the same orbit, thus allowing us the ability to harness the power via satellite or live in the orbit. Pretty easy, yes?
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Next we have DEFCON 2 of the Dyson Sphere theory (above). In this instance, multiple satellites are projected 15 degrees relative to one another, thus increasing the amount of energy you could harness.
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Next is the Dyson Bubble concept where each satellite and/or space habitat is individually independent of one another. All of these concepts have some obvious advantages, seeing as each individual location could be built over an extended period of time.
Similar variations of this concept has been thrown around, specifically with future-science author Larry Niven and his early 70's story Ringworld (pictured below).
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1959.
Let me write it again...1959...on a napkin.
Even though it's been said that the sphere concept is a bit dubious in scale (apparently there are some small gravity issues), the swarm and bubble concepts are potentially feasible. Can you imagine?
Not bad for a guy who developed these theories long before we landed on the moon...it's kind of like Euclid mapping out the potential of a Pentium 4.
In the interest of full disclosure, however, I'll also let you know that he also thinks there's no reason to worry about global warming. As a result, I guess there's a long-standing quack or genius debate.
Which camp are you in?