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IBM and SAP open up big data platforms for citizen science

IBM and SAP open up big data platforms for citizen science | Science | Scoop.it
IT companies are making enterprise technology available to citizen projects that could benefit both the environment and business (MT @GuardianSustBiz: IBM & SAP open up #bigdata platforms for citizen #science.
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von Neumann probes, Dyson spheres, exploratory engineering and the Fermi paradox

Fermi paradox: Our universe is fairly old - where are all the aliens? 

 

The Fermi paradox is the contrast between the high estimate of the likelihood of extraterritorial civilizations, and the lack of visible evidence of them. But what sort of evidence should we expect to see? This is what exploratory engineering can tell us, giving us estimates of what kind of cosmic structures are plausibly constructable by advanced civilizations, and what traces they would leave. Based on our current knowledge, it seems that it would be easy for such a civilization to rapidly occupy vast swathes of the universe in a visible fashion. There are game-theoretic reasons to suppose that they would do so. This leads to a worsening of the Fermi paradox, reducing the likelihood of "advanced but unseen" civilizations, even in other galaxies.

 

Oxford University physicist Stuart Armstrong has devised a rather ingenious and startling simple plan for doing so-one which he claims is almost within humanity's collective skill-set. Armstrong's plan sees five primary stages of construction, which when used in a cyclical manner, would result in increasingly efficient, and even exponentially growing, construction rates such that the entire project could be completed within a few decades. Broken down into five basic steps, the construction cycle looks like this:

 

Get energyMine MercuryGet materials into orbitMake solar collectorsExtract energy

 

The idea is to build the entire swarm in iterative steps and not all at once. We would only need to build a small section of the Dyson sphere to provide the energy requirements for the rest of the project. Thus, construction efficiency will increase over time as the project progresses. "We could do it now," says Armstrong. It's just a question of materials and automation.

 

And yes, you read that right: we're going to have to mine materials from Mercury. Actually, we'll likely have to take the whole planet apart. The Dyson sphere will require a horrendous amount of material-so much so, in fact, that, should we want to completely envelope the sun, we are going to have to disassemble not just Mercury, but Venus, some of the outer planets, and any nearby asteroids as well.

 

Why Mercury first? According to Armstrong, we need a convenient source of material close to the sun. Moreover, it has a good base of elements for our needs. Mercury has a mass of 3.3x10^23 kg. Slightly more than half of its mass is usable, namely iron and oxygen, which can be used as a reasonable construction material (i.e. hematite). So, the useful mass of Mercury is 1.7x10^23 kg, which, once mined, transported into space, and converted into solar captors, would create a total surface area of 245g/m2. This Phase 1 swarm would be placed in orbit around Mercury and would provide a reasonable amount of reflective surface area for energy extraction.

 

There are five fundamental, but fairly conservative, assumptions that Armstrong relies upon for this plan. First, he assumes it will take ten years to process and position the extracted material. Second, that 51.9% of Mercury's mass is in fact usable. Third, that there will be 1/10 efficiency for moving material off planet (with the remainder going into breaking chemical bonds and mining). Fourth, that we'll get about 1/3 efficiency out of the solar panels. And lastly, that the first section of the Dyson sphere will consist of a modest 1 km2 surface area. And here's where it gets interesting: Construction efficiency will at this point start to improve at an exponential rate.

 

Consequently, Armstrong suggests that we break the project down into what he calls "ten year surges." Basically, we should take the first ten years to build the first array, and then, using the energy from that initial swarm, fuel the rest of the project. Using such a schema, Mercury could be completely dismantled in about four ten-year cycles. In other words, we could create a Dyson swarm that consists of more than half of the mass of Mercury in forty years! And should we wish to continue, if would only take about a year to disassemble Venus.

 

And assuming we go all the way and envelope the entire sun, we would eventually have access to 3.8x10^26 Watts of energy.


Via Dr. Stefan Gruenwald
marcel blattner's insight:

Speculative but worth thinking about seriously. 

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Down the rabbit hole of antimatter, or how to believe six impossible things about gender stereotypes before breakfast.
marcel blattner's insight:
Very nicely written
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