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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.
You can advertise in this sig from as little as £99.99 a month!
I was watching that Riddick movie with the Necromongers the other day and I realized that the concept was actually very realistic. What kind of society would get into space first? The ones that put a high priority on space exploration. And what kind of civilization would do that just for the heck of it before any others? The ones that have some irrational reason to do it driven by some kind of religious fervor. While the "Star Trek like" science-driven societies pace themselves in a sensible manner, the religious nutjobs would throw every single resource their entire civilization could at getting into space to please their space deity or whatever. If there's an advanced space-faring race out there you probably want to steer clear of them.
See also: The Irkens from Invader Zim
"When information is power, privacy is freedom" - Jah-Wren Ryel
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.
A star is a fusion reactor. In fact, if you need the kind of power that's given out by a Dyson sphere, then a Dyson sphere is by and large the most efficient method for generating it, especially for long periods of time.
The question should be whether any civilization would require so much power in such a static and concentrated way (as opposed to dispersed across hundreds of planets across thousands of lightyears), and where they'd find the materials required to build it (we're speaking about transforming entire planets from crust to core, or harvesting dozens more in a less destructive fashion).
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
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.
Right, because there's no way a civilization advanced enough to build 282743338860000000 square kilometers of solar panels is going to be able to build solar panels capable of absorbing and using mid-infrared light (heat). If the supposition is that they inevitably build Dyson spheres to capture all of the available energy coming off their star, why would they let a whole bunch of it escape as heat?
Seems like a giant waste of time and money, but I suppose they will be generating useful data while they look. Still, their chances of finding one are likely ludicrously close to zero even if one does exist. I also find the whole premise to be rather poorly thought out, I have to admit; even if a civilization is capable of building a Dyson sphere, I'm not sure it makes any sense to actually do it.
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
Further, in the traditionally-envisioned model of the Dyson Sphere (hollow sphere around a star; not Dyson's actual theory), the livable surface area of the sphere would come out to something on the order of millions of Earth-sized planets. Population control at that scale, for a society with that kind of capability, is essentially a non-issue for any reasonable length of time.
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
First off a dyson sphere does not take into account the MASSIVE amount of praticle energy that is coming off the star. the Stellar wind on that scale would be immense. Secondly, Orbits are not magical. a dyson sphere is unstable and will either wobble and start to collapse into the star, or rip apart due to the uneven gravity well. Just the technology to even be able to have the ability to think of building a Ringworld, something far, far, FAR easier than a Dyson sphere is so mind bogglingly compex that it collapses in upon it's self.
Sorry but it's a waste of time we might as well look for civilizations that are harvesting black holes to power their space ships.
Do not look at laser with remaining good eye.
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
I don't understand this nonsense of astronomers searching the galaxy for Dyson Spheres. I had no trouble finding and buying one off Amazon. The design is revolutionary, and it's very powerful. It gets pet hairs out of my carpet with ease. Highly recommended!
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!
Small black holes are basically 100% efficient at turning mass into energy via Hawking Radiation, which is nearly two orders of magnitude more efficient than Stars powered by fusion.
There are some serious suggestions as to how to go about making them (ultra powerful converging gamma ray lasers, as photons aren't subject to Pauli Exclusion Principle). While it probably requires a moon-sized machine to do it, it is probably feasible for a civilisation capable of building a Dyson sphere, and once you have that technology you don't need stars or the gravitational hassles that they create anymore.
If the civilization has achieved 100% energy efficiency, there would be no radiated heat, as that is simply wasteful.
Fundamental laws of physics apply, even if you're a technologically advanced civilization.
Although a star has a large net output, it's only because it's so big. Proton-proton fusion has a very low energy density. Though barely conceivable by today's technology, you could theoretically produce the Sun's output in a powerplant a few km across going to D-D or P-11B fusion fuel. No stars are therefore necessary. Matter-antimatter reactions would be orders of magnitude better still.
Don't worry; we're working on that.
When someone says, "Any fool can see
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.
Been written about. Course, Zahn didn't come up with any conclusions why the Spinneret aliens were hiding, just that they were.
Makes me wonder if some civilisations are hiding, and what they're hiding from.
Understanding the scope of the problem is the first step on the path to true panic.
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.
We build taller and taller skyscrapers. Why? There are more efficient structures, and it's not like they are there to harvest resources unavailable at ground level. Besides, some peasant can build a mountainside hut that is at a higher altitude than the highest skyscraper. So, maybe it's not about the energy. Maybe it's a statement of prowess, or art.
When our name is on the back of your car, we're behind you all the way!
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.
We cannot (given current understanding and resource consumption patters) maintain the current population of the planet indefinitely.
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
Would it? The technology required to build any kind of Dyson sphere and the technology required to move a large population to another star are both so far beyond our own capability that there is little basis to judge which is easiest.
You build a box and try to fit God inside it. When he doesn't fit, you conclude he doesn't exist. The irony is that God created the one who created the box in which God does not fit. I find that you are not even aware of your own presuppositions, therefore you cannot reach a reasonable conclusion. You have been so heavily influenced by atheists and scientism (which is practically worshipped as a religion unto itself) that you have confined your own thinking to a box which you are unwilling to exit, and perhaps even unaware of.
1. You presuppose that if God acts on a prayer, it indicates that he was previously unaware of something.
2. You presuppose that if God is all-knowing and good that he must necessarily enforce what is best for people.
3. You presuppose that, as a finite, relatively insignificant human being, you could possibly know whether and when God intercedes in our world and to what ends.
4. You presuppose that you could even know what is "good" or "best" from the perspective of an all-knowing, all-powerful, universe-creating, life-breathing entity beyond our comprehension.
Your conclusion ("Therefore we find that an all-knowing and good god cannot be influenced by prayers...") is a non sequitur. It's not even a logical conclusion from your assertions. And your assertions are unsubstantiated, anyway.
The very nature of an omnipotent, omniscient entity who exists outside of our plane of existence means that we cannot completely comprehend him; we may only do so to the extent he chooses to reveal himself to us. What you have done is set forth arbitrary specifications for God, and if it seems to you that he does not meet your criteria, you conclude that he must not exist. This is nothing short of absurd. If God exists outside of or above our universe, if he created you and the universe and the very nature of our existence, how could you possibly define the means by which he may exist?
N.B. I am not even arguing that God does exist--I'm simply arguing that your logic is fundamentally flawed because of your presuppositions. Either God is an all-powerful, all-knowing entity--and therefore beyond our comprehension--or he is finite, like us, but with advanced technology--and therefore, presumably, ultimately understandable--or he does not exist at all. If you are arguing based on the presupposition that he is all-powerful and all-knowing, then you must argue that he is far beyond any of your reasoning or standards, and therefore you cannot logically define criteria for proving his existence.
The argument boils down to whether anything can exist beyond our understanding or comprehension: if we can comprehend God, then nothing is ultimately beyond our understanding, and--eventually, perhaps far beyond our lifetimes--we can "find" him, understand him, and even possess similar powers (note that this implies being able to create an entire universe of our own, from nothing). In this case, it's simply a matter of time until he is "discovered"--until then, he either does not exist or we have yet to find him (a conclusion which does not answer the questions, "How?", "Why?", and "From what?"). But on the other hand, if things may exist beyond our understanding, then we can never expect to meet God on our terms, and trying to do so is naive and futile.
I like the fishbowl analogy. (It's not perfect, of course.) The fish's entire universe is inside his fishbowl. He knows nothing outside of it (perhaps it would be useful to declare the fishbowl to be opaque, or at least barely translucent). Now and then something from outside his universe seems to interact with his world--perhaps a hand reaches in, but he cannot discern the source of the hand. The fish cannot comprehend existence outside of his bowl, or outside of water, the very fabric of his existence. Therefore, to him, nothing must exist outside of his world, and nothing must exist outside of water--which, to him, isn't even water, just reality as he knows it. But to the human, clearly the fish is limited
"Those who consume the bulk of goods are those who make them. We must never forget this secret of our prosperity."