Slashdot Mirror
Advanced Civilizations Probably Don't Exist In Our Galactic Neighborhood
schwit1 writes: New observations of the best candidate galaxies now suggest that advanced civilizations are very rare or don't exist in the local universe. Researchers looked at several hundred nearby galaxies that emitted a high amount of mid-infrared radiation (abstract), which could possibly be produced as the waste heat from civilizations using energy on galactic scales.
They found: "The presence of radio emission at the levels expected from the correlation, suggests that the mid-IR emission is not heat from alien factories but more likely emission from dust — for example, dust generated and heated by regions of massive star formation. As Professor Garrett explains: 'the original research at Penn State has already told us that such systems are very rare but the new analysis suggests that this is probably an understatement, and that advanced Kardashev Type III civilizations basically don't exist in the local Universe.'"
Obviously, the uncertainty of these results is quite high. Nonetheless, the results indicate that either humanity really is the only intelligent species in this part of the universe, or advanced civilizations are far more efficient in their use of energy than is reasonable to assume.
They found: "The presence of radio emission at the levels expected from the correlation, suggests that the mid-IR emission is not heat from alien factories but more likely emission from dust — for example, dust generated and heated by regions of massive star formation. As Professor Garrett explains: 'the original research at Penn State has already told us that such systems are very rare but the new analysis suggests that this is probably an understatement, and that advanced Kardashev Type III civilizations basically don't exist in the local Universe.'"
Obviously, the uncertainty of these results is quite high. Nonetheless, the results indicate that either humanity really is the only intelligent species in this part of the universe, or advanced civilizations are far more efficient in their use of energy than is reasonable to assume.
Mmmno. The research doesn't indicate anything like that at all. They were looking for civilizations that harness energy and resources at galactic scales, ie. Kardashev III - level civilizations. Mankind haven't even reached Kardashev I yet. The submitter didn't understand what they were reading and jumped to conclusions.
Efficiency can only get you so far. You use enough energy, you will get waste heat as entropy, and entropy is inescapable. Of course, they might use hyperspatial redirection or subspace quantum oscillation phase modulation or something to make it look different to us or send it to another pocket dimension, but chances are, we'd have some indication of a Type III civilization.
What we should really be calling the summary out on is the fact that they equate a Type III civilization with an "advanced civilization". Yeah, it's advanced all right, but the bloody United Federation of Planets would only be something like a Type II. You have to control the energy output of an *entire galaxy* to be a Type III.
I'm no expert, but I remember reading that digital communication is virtually undetectable at galactic distances, because it fades way more quickly and becomes indistinguishable from background noise.
Nah, it's worse than that. Spectrum is finite, so the incentive over time is to use interesting encoding techniques to smear the data across the available spectrum. If you don't know the protocols, a given frequency mostly looks like noise in the time domain. And there are similar incentives to fill up the frequency domain. And there's incentive to use lower power, so that more transmitters can share the frequency, so those are all going to merge into a mess, too.
Basically, by design our radio output is tending towards noise which will be impossible to differentiate from a light year away.