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Astronomers Search For Dyson Spheres of Alien Civilizations
Hugh Pickens writes "An article by Ross Andersen makes note of Freeman Dyson's prediction in 1960 that every civilization in the Universe eventually runs out of energy on its home planet, a major hurdle in a civilization's evolution. Dyson argued that all those who leap over it do so in precisely the same way: they build a massive collector of starlight, a shell of solar panels to surround their home star. Last month astronomers began a two-year search for Dyson Spheres, a search that will span the Milky Way, along with millions of other galaxies. The search is funded by a sizable grant from the Templeton Foundation, a philanthropic organization that funds research on the 'big questions' that face humanity, questions relating to 'human purpose and ultimate reality.' Compared with SETI, a search for Dyson Spheres assumes that the larger the civilization, the more energy it uses and the more heat it re-radiates. If Dyson Spheres exist, they promise to give off a very particular kind of heat signature, a signature that we should be able to see through our infrared telescopes. 'A Dyson Sphere would appear very bright in the mid-infrared,' says project leader Jason Wright. 'Just like your body, which is invisible in the dark, but shines brightly in mid-infrared goggles.' A civilization that built a Dyson Sphere would have to go to great lengths to avoid detection, building massive radiators that give off heat so cool it would be undetectable, a solution that would involve building a sphere that was a hundred times larger than necessary. 'If a civilization wants to hide, it's certainly possible to hide,' says Wright, 'but it requires massive amounts of deliberate engineering across an entire civilization.'"
Dyson assumed that all alien civilizations are stupid enough to believe in infinite growth, much like humanity.
I don't believe this. I think the most advanced aliens have probably realized that there isn't much point of growth after a certain threshold.
They'll find nothing.
where would you get enough matter
Obviously harvested from the home planets of other civilizations they've destroyed. What a silly question.
The energy output of a star is going to be many orders of magnitude higher than what you'd get from fusion technology. The sun is a giant fusion plant itself! A sufficiently advanced technological civilisation may very well find itself bound only by the amount of energy it could produce or harness, and getting every last scrap of energy from a star is a massive boost to an energy based economy.
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I think you are 100% correct, but it's not just politicians who are small minded. Here's an example. I work in IT as a Linux System Administrator. One of my colleagues is not only extremely smart and one of the most knowledgeable IT guys I've ever worked with (he is like a living set of man pages), he is into sci fi. He feels very strongly that we have more pressing needs at home in the USA than to spend almost any money on NASA. I mean, he is the exact kind of guy who I would expect to be in favor of building a moon base. When guys like him won't even back NASA, there's really no hope for the USA to ever do anything useful in space in our lifetime unless it becomes a national security concern. But in direct response to your suggestion, I want to see a moon base first and a manned expedition to Mars before we try something massive like this. It's a "walk before you run" kind of thing.
That's only given all civilizations started at roughly the same time. However, this isn't Civilization V. A space-faring race could have formed a contigous civilization several hundred thousands or millions of years ago, not a couple thousand years like ours. It might be the natural evolution of things at that point.
Dyson doesn't have spheres, Dyson has balls !
But nothing sucks like an Elecrolux.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Eventually, the energy is converted to heat, which can leak out into space. Our planet is not a closed system. The good thing is that there is also energy coming in into our system (solar energy, for example).
Nae king! Nae laird! Nae yurrupiean pressedent! We willna be fooled again!
Imagine what the Republicans and Tea Party would do and say if somebody proposed government-enforced limits in the USA.
Why pick on the Republicans here? I'm relatively liberal, and I know plenty of other liberals who would be just as outraged.
Obligatory, of of course
Energy can't be used for work, only energy difference can. If they didn't radiate away the captured sunlight they would overheat very quickly.
Against Stupidity, even the gods themselves labor in vain.
lets see how many mods perceive the relevance to the reference
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
Quick! Let's build a giant IR emitter w/ some filters to produce the same spectral curve as a Dyson sphere. All those not-quite-advanced societies out there will detect it and run screaming from our perceived galactic-overlordishness.
https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
For fuck's sake, people, read a god damn book. Star Trek is make-believe bullshit.
If you're completely ignorant about a subject, is it too much to ask that you remedy the situation before farting an opinion? There are four links in the post for your education!
I mean, sure, the Templeton Foundation are a bunch of religious loons, but do you actually think you know better than Freeman Dyson and the actual physicists, astronomers, and engineers who consider the idea plausible? If so, you'd better tell them why it can't work, before they waste all that money! Your paper on the subject will make you famous!
There really is no way to build a 0.35mm steel plate in space for more than 500 miles without it collapsing into a rubble pile.
Dyson was well aware of that. A Dyson Sphere is not a connected solid sphere. It can consist of billions or trillions of independently orbiting structures, such as O'Neill Cylinders.
A solid structure would be a Ringworld, which is impossible to construct with our current understanding of reality.
Matter-antimatter reactions may have extremely high power density, but there's a big problem: where do you get the antimatter from? It's unlikely there's large naturally-occurring deposits of it available anywhere, since it annihilates itself when it contacts matter. M-A energy sources really only make sense as a way of storing energy, not producing it. Even Star Trek takes this position: the starships use antimatter for propulsion, but only because of the energy/power density it offers, and it's produced artificially specifically for this purpose, probably using solar energy production.
Energy is a primary need of any civilization. Every civilization has to get it somewhere. Back in the early days, we got our energy from the sun solely: we used it to grow crops (for food) and feed our animals (for transportation), and to power our ships (for water-based transportation; we used the sun to produce wind to power these ships; luckily, we didn't have to produce the wind ourselves, as natural processes had already done this for us, but we took advantage of it). These days, we largely get our energy from hydrocarbons created millions of years ago by solar-fueled processes, though we're getting some power from nuclear fission (where we break apart large atoms that were created in stars long ago). In short, we get energy where we can find it naturally-occurring. A more advanced civilization will probably be no different: though it may convert energy from one form to another, it'll have to mine that energy from somewhere, and the most obvious source is a nearby star which is giving off lots of energy for free already. Of course, if they figure out how to get energy directly from quantum fluctuations, or by mining antimatter from a parallel universe or something, then they might not need stars any more, but that sounds even more advanced than a Kardashev Class II civilization which we're talking about here.
You have to release heat. The laws of thermodynamics demand it ; even if you have a fractally complex energy usage system, it has to move outwards, or it will all grind to a halt. So you'd see a large sphere at a temperature somewhere above cosmic background - how far above would depend on the efficiency of their engineering.
Of course, this presumes that advanced civilizations will simply re-radiate the left-over thermal energy, it's entirely possible that they would have close to 100% efficient systems or have a economically sensible way of storing thermal energy to re-use at a later date.
It also presumes that advanced civilizations would waste their time and resources building such a contraption, when, given the technology necessary to do so, it would be far easier to find another planet.
The level of sophistication necessary to deploy such a thing would require a level of technology where Fusion is childs play. There would be no energy shortage.
Sig Battery depleted. Reverting to safe mode.
The Nazis got us into space. The military industrial complex got us the internet. War gave us most of our trama medicine.
But you take issue with this one, huh?
THL phish sticks