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Why We're Looking For ET All Wrong
StartsWithABang writes: When you consider that there are definitely millions of planets in the habitable zones of their stars within our Milky Way galaxy alone, the possibility that there's intelligent life on at least one of them, right now, is tantalizing. But we're in our technological infancy, relatively speaking, having only been broadcasting electromagnetic signatures visible by an alien civilization for around 80 years. Unsurprisingly, we're looking for exactly the types of signals we're capable of sending, but what if that's totally wrongheaded? Based on how technology is evolving and what the Universe is capable of, perhaps we should be looking not at electromagnetic radiation, but neutrino or gravitational wave signals from the distant Universe to search for alien civilizations.
While we have been sending radio transmissions for 80 years, the modularion has changed dramatically, which has negative imolications for finding ET, even if they are using our same frequency bands.
Early on we used FM and AM. Both end up with a strong easy to identify carrier tone. As time has gone one and DSP has become a cheap commodity we moved to more efficient modulations (relative to Shannons's limit). Digital modulations look more noise like and have no carrier as such. GPS is below the noise floor as received due to the energy being so smeared out, and that is from medium earth orbit. Your voice calls are recieved below noise as well in a CDMA system.
So if ET is similarly good at math, they will have moved on to signals that are similarly noise like and may simply be undetectable. There may only be a 100 year or so window to detect Earth, and similar may be true for ET.
One day, scientists and their followers will feel like complete idiots, when it becomes obvious aliens have been here all along.
Citation#1: US presidents have known about UFOs here on Earth, even seen them:
https://www.youtube.com/watch?...
Citation#2: If 200+ NASA, Ex-Military, Ex-US government high ranking employees coming forth and willing to testify before congress isn't enough for you, then your mind is too closed: https://www.youtube.com/watch?...
Citation#3: How many pilot witnesses with radar evidence to back it up does it take before you belive that UFOs are real and here on Earth?
https://www.youtube.com/watch?...
Citation#4: Is 3 Million alien abductions in the USA alone enough evidence for you, or are you waiting around for a nice round number like 10 million?
http://www.ufoevidence.org/top...
No trees were killed in the making of this post; however, many trillions of electrons were horribly inconvenienced.
One aspect of the Fermi Paradox is the assumption that "civilization as we know it" necessarily broadcasts a huge amount of information-bearing electromagnetic radiation, and that more advanced civilizations will broadcast more. From a modern perspective, this seems silly.
A signal recognizable across interstellar distances represents waste. It's energy that's spent without reaching its intended target. One aspect of "advancement" is reducing this waste -- improving modulation schemes, encoding efficiencies, and transmission techniques to minimize wasted power.
A signal recognizable across interstellar distances also represents lack of diversity, or wasted capacity. If you're using a certain chunk of spectrum to broadcast a signal recognizable across light-years, you're not getting as much capacity out of that chunk as you could by using it for a bunch of geographically localized broadcasts -- for example, by broadcasting separate programs to each of 100 individual square miles within a 10-mile square, rather than one program for the entire 100-square-mile area. Take this idea a bit further, and you see our current cellular networks. From space, their signals would sound like noise.
It seems to me that the natural signal of a civilization like ours is a pulse of EM broadcast, lasting perhaps a few decades, then going silent or becoming indistinguishable from noise as we move to more localized and more efficiently encoded transmissions. If nobody happens to be listening in our direction during the right interval, brief compared to technological civilization's lifespan, they could easily miss us completely.