Antropic Principle and Extraterrestrial Life

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It is my personal beleif that there is an abundance of life thoughut our galaxy, but I'm interested in other takes on this problem.

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That is my "belief" as well. I would phrase it thus "I think that it is highly probable that life exists on other planets". Right now all we can do call it a probability or speculation, but I have no problem with that.The bigger question is whether or not we will ever be able to know if life exists outside of our solar system. SETI, for example, is searching for INTELLIGENT life by detecting non-terrestrial radio signals, and I believe more recently, laser signals. The tougher search is for non-intelligent life. Not only is the speed of light a universal speed limit, it also puts a large obstacle in the way of research outside of our solar system. Life on other planets may be a question that we are never able to answer, that is unless signs of life are found on Mars or Europa.

Since we are all throwing crazy ideas around, I thought I would join in.The first hurdle for a detectable society is technology. We are focusing on laser and radio waves because this is what humans use. We also assume that societies will use these forms of communication at intensities that would be detectable from great distances. All of these are anthropic assumptions. As our technology advances we may find that, as Jar mentioned, the window of opportunity for detection is only a few centuries long. This is a huge problem.The second hurdle is for a society to survive the advent of technology. Humans have narrowly missed an all out nuclear war on at least one occasion (Cuban Missle Crisis). There is no guarantee that other societies have not offed themselves due to harnessing the power of the atom or other technologies.The third hurdle is interstellar travel. We have all grown up with Star Trek, Star Wars, and Battlestar Gallactica. We all assume that fast, interstellar travel is a viable technology. In reality, we have no evidence that interstellar travel is either economically viable or technologically possible. Travelling even at 0.5 c poses radiation problems since harmless wave lengths will be blue shifted into harmful wavelengths. Travelling at slow speeds requires either hibernation or a large amount of supplies. It is much more economically viable to colonize within the solar system, IMHO, than to look elsewhere in the solar system. A Mars colony will save humanity from supervolcanoes and large meteor strikes. However, a Mars colony will not save us from an our sun when it dies and expands outwards.Just on a hunch, the rise of sapient and intelligent species across the galaxy may be common but detection of these societies may be next to impossible. They may kill themselves off, die off with the death of their sun, or a combination of other factors. Being a gregarious species we like to assume that we are not alone, and we probably aren't. However, saying hi to the neighbors may never happen.