The Fermi Paradox and the Drake Equation
Enrico Fermi, the flamboyant “Physicist with an F” as he would say, had a startling revelation one day. “The apparent size and age of the universe suggest that many technologically advanced extraterrestrial civilizations ought to exist. However, this hypothesis seems inconsistent with the lack of observational evidence to support it.” It would not take a lot of time compared to the age of the universe to have covered it in a star spanning Empire. Why, then, were there no alien civilizations out there already? The Drake Equation can make very high estimates of the amount of intelligent life in the Universe or even in just our galaxy. Why can’t we hear the chatter of alien civilizations?
The fact is that SETI didn’t start until 1959. All sky survey’s have had the assumption that beacons would be continuous. So, all parts of the sky have been looked at for just moments of a time at random intervals since 1959.
The Wow! Signal
For some reason this topic has been coming up in my social media networks a lot and has gotten me to think about it as well. Does Firmi’s Paradox still hold or have we already found proof of alien life? The only credible point of evidence is the Wow! Signal, detected by Big Ear in 1977. It was a narrow band, strong signal, near the frequency of the precession of hydrogen. It was exactly what scientist would hope to find. Its the message we have sent as well. However, there is this disturbing bit of news that comes with it: The signal appears to have come from an area of the sky with no stars or planets, northwest of the globular cluster M55. The signal was also required a quite powerful transmitter at 2.2 Gigawatts. That kind of power is achievable with nuclear power, but is quite expensive and not likely to be kept on all the time. However, it is strong enough to be seen across the galaxy.
The Wow! signal has never been heard again. It lasted at most 24 hours and as little as dozens of minutes.
Humans are curious. We love exploration of ideas. We love knowing new things, because that helps us advance. The reason we want to know if ET exists is fundamental to our nature. However, in looking back at our own history of discovering “alien cultures” here on Earth, we are cautious. We know what colonization looks like. We have no record of what happened to Neanderthal man, yet, but all indications are that it did not end peacefully for them, as Homo Sapiens expanded into the World. However, some optimists have imagined wise and peaceful ETs out there. Others contend there can only be paranoid fear and our only true visitation by aliens will be via Relativistic Kill Vehicles, sent to sterilize our planet.
Lets Play Interstellar Identify Friend or Foe
In this game, lets assume just two players. One is an alien civilization that has decided to become known. What isn’t known is if they are friendly or hostile. We don’t assume the civilization is a non-broadcaster because not broadcasting is one of your choices and leads to a very quiet galaxy (which we currently have.) Why would a hostile agency broadcast at all? They want to find other alien agencies and need to lure them in. They are hostile because they are paranoid about the other forms of life out there. Their response is to follow up detection with relativistic kill vehicles (perhaps using asteroids that they get up to speed and destroy the planets in the solar system of their enemy. Not hard because gravity is a predictable effect, giving all the targeting information one needs.)
A friendly civilization is interested in information exchange. The more information they have the better. While there are risks in full disclosure, even between friendly agencies, they are outweighed by the benefits of mutual information exchange. That Full Disclosure communication, however, is heard by everyone, which is an important point.
There are three broadcasting levels. The first is a total blackout with passive listening only. The second is intermittent signals, broadcast loudly, but far away from the home system. This is most like the Wow! Signal. Finally there is constant Full Disclosure broadcast. This is like some people on Facebook! Those smart people at SETI and NASA have been doing this: loudly telling the Universe where we live, that we still have internecine warfare, our biological make up, and that we still worship cats and Kardashians.
Lets use game theory to understand the consequences here. I did my work in a spreadsheet which I’ll add as images. If you want the spreadsheet just get it from here.
Here in Game 1 we see what happens when we broadcast. So if we were Silent (row 1) and the other agency was an Intermittent broadcaster (column 2) our result would be ND, PD which is read as, Player 1 is Not Detected, Player 2 is Partially Detected. That means that Player 1 knows Player 2 exists but not much else. This is still useful information. Player 2 is unaware of Player 1. This game is simple and obvious and we don’t assign any value to the choices, just consequences. Understanding those consequences requires a more indepth understanding of basic desire. Perhaps I over-simplify, but an agency is going to be either hostile or friendly. Hostility, here, is defined as paranoid of competition. Friendly is defined here as seeking information exchange. Would this be possible without faster than light communication? I don’t have an answer for that. Let’s assume once communication is established, it eventually will have a positive payback between friendly agencies.
Since we must assume one side is breaking intergalactic radio silence, here is how I think it plays out.
The Infinite Cost Scenario is where you were detected by the other agency and they opted to sterilize your planet with a relativistic weapon. Since player 1 (left side) has the choice to produce a signal or not, we limit the 2nd player (top row choices) to partial or full disclosure. I would like to point out that NASA has already chosen the Partial Disclosure, with possible Full Disclosure. This gives us a 25% to 50% chance of being visited by a Relativistic Kill Vehicle in the next 800 to 1000 years. You’re Welcome. Of course it also has the chance to give us full and friendly relations with wise and benevolent space beings. People thousands of years into the future, you too are welcome!
How Close are we to Extinction via RKV?
I take our neutrality in this matter as a fact. I think we might consider open and fruitful conversation with alien people. Then again I also look at how some people treat other people who think even modestly differently on this planet… and I consider us more likely to be hostile. That said, looking at the chart I see two Nash Equilibrium in the mix. If the signal came from a hostile force, they have risk that we will determine their location, however, they are hoping for us to just be all open and fully disclosed so they can smash our home planet to pieces. If we suspect them to be hostile we prefer a zero disclosure strategy. If they are friendly, we benefit with full disclosure. Of course there is a risk not covered in this analysis. What if there is a third party, definitely hostile, and not doing anything to reveal themselves? Two parties blabbing on about nerd science crap in the bandwidth around Hydrogen are now going to both be targeted. Again, Thanks NASA and SETI.
But it’s not all bad. Maybe everyone leaks information and we just haven’t invented the right equipment yet to hear them. Removing the ND options reveals that there are low risks in PD. You gain information that you aren’t alone. However Full Disclosure brings Infinite Cost risks. In the last block I look at what a stealth agency gets. It is all gravy. In fact it favors being a hostile jerk. So, if that is the case then the Universe is divided into two camps. Hostile Jerks who lay low and snipe at your civilization versus Nerds who share everything and get removed from the gene pool. Thanks NASA nerds! Now I can sleep tonight knowing you have doomed us. On the upside, the most dangerous hostiles are the ones who send no signal, so its quite possible the Wow! Signal was a genuine friendly message. As stated above, I give us 50-50 odds that if it was a signal from extraterrestrial intelligence, it’s friendly.
The Wow! signal was sent from empty interstellar space. It was broadcast with an antenna the size of the Arecibo Observatory and powered by a nuclear power plant strong enough to power New York City. We can’t even come close to doing that. Not. Even. Close. So, I think it’s a lure. After doing the above analysis, it’s a lure for dumb civilizations to raise their hands and volunteer for extinction. Now, we can’t create a signal strong enough to compete with Wow! And if we ever get better at broadcasting into space we should seriously reconsider doing that. Certainly not from Earth. Certainly not communicating that we are organic life living on a water rich planet…
Other possibility exists. What if a hostile race discovered one trying to be silent? They could position a beacon designed to encourage contact from other agencies that would then investigate and find the hiding alien intelligence. If they were friendly with each other then the silent one would kill two birds with simultaneous attacks. If one was hostile then they would use that in the future to direct this violent species to attack neutral ones, letting them do the dirty work and then destroy them once they were no longer useful or too much of a threat.
Prisoners Dilemma and Alien Contact: Harold P. de Vladar (2013). The game of active search for extra-terrestrial intelligence: breaking the ‘Great Silence’. International Journal of Astrobiology, 12, pp 53-62. doi:10.1017/S1473550412000407.
Less nerdy version of above: http://www.newscientist.com/article/mg21628954.200-search-for-aliens-poses-game-theory-dilemma.html#.VWY-KkbmwRl
Pessimistic Viewpoint: http://www.teamliquid.net/forum/general/300793-game-theory-applied-to-aliens
Wikipedia on the Wow! Signal: http://en.wikipedia.org/wiki/Wow!_signal
Skeptoid Podcast (one of my favorites) on the validity of the Wow! Signal being from extraterrestrial intelligence: http://skeptoid.com/episodes/4342
Image of the actual Wow! Signal printout: http://www.bigear.org/Wow30th/WowL.jpg
National Geographic on post Wow! Signal searching: http://channel.nationalgeographic.com/chasing-ufos/articles/what-is-the-wow-signal/
An astronomer believes Wow! is a lighthouse http://zeenews.india.com/news/space/wow-signal-came-from-space-lighthouse_759218.html
Crank astronomer states we should have found the signal again, even though we only send one every few decades… http://www.damninteresting.com/the-wow-signal/
How to make your own Big Ear observatory and look for Wow! signals: http://www.setileague.org/articles/calibwow.htm
Skeptical thoughts on what else Wow! could have been: https://lflank.wordpress.com/2015/02/12/the-wow-signal/
Full on NERD after action report, by Dr. Ehman himself, discoverer of the Wow! signal: http://www.bigear.org/Wow30th/wow30th.htm