This question is not directed at members of RHP, but a reference to what is known in astronomy as the Fermi paradox. This paradox, first posited by Enrico Fermi, (roughly) states that given that the lifespan of the universe is large (now known to be approximately 13 billion years) and that in a relatively short span of time (maybe 100 thousand years) humans have evolved from the basics of social organization to a space-faring race, and also given the enormous number of planets thought to be in our galaxy (more and more are discovered each day, even with the rudimentary indirect detection method of seeing the planets' gravitational effect on stars) that if they exist elsewhere, some other intelligent life should already have developed interstellar travel and colonized the galaxy, leaving detectable traces of their existence.
Since we have not detected any evidence of extraterrestrial intelligence (or even of extraterrestrial life, so far) this leaves several possibilities. First, that we are on the only planet in the galaxy that contains life. Second, that many planets in the galaxy contain life, but we are the only one that has any intelligent beings on it. Third, that other intelligences exist, but we are the most advanced. Fourth, other intelligences more advanced than we are exist, but have for some reason not chosen to colonize the galaxy. Fifth, that other intelligences have, in fact, colonized the galaxy, but we lack the technological means to detect their presence. Sixth, that extraterrestrial galactic civilizations have not come close enough to earth to be detected. Seventh, that they have come close enough to earth to be detected, but have chosen to hide their presence from us.
I'm sure I'm leaving out a bunch of possibilities. I just wanted to hear people's thoughts on this issue, and see which explanation people felt makes the most sense.
-mike
Originally posted by legionnaireI'm sure there are extraterrestrial life forms on other planets somewhere because there are way more then 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
This question is not directed at members of RHP, but a reference to what is known in astronomy as the Fermi paradox. This paradox, first posited by Enrico Fermi, (roughly) states that given that the lifespan of the universe is large (n ...[text shortened]... d see which explanation people felt makes the most sense.
-mike
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000's(Centillion's(1 followed by 303 zeros) of galaxys out there.
but as long as they dont try and invade us I dont mind them being there😉
I think another possibility is that there could be a tendency for advanced societies to annihilate themselves not long after they discover the technology that enables them to spread through the galaxy or announce their presence, either deliberately or through the spillage of radio waves/tv pictures and so on.
Look at this planet - we have had the weapons to self-destruct for only a few decades and we have come terrifingly close on occasion. We can't say with any confidence that we won't do so within 20 years, 50 years, 100 years, 150 years....
The other threat to planetary life is a massive asteroid strike, just ask the dinosaurs. Not so rare in a geological time-frame and may knock out some civilisations before they have the opportunity to construct some kind of defence.
Finally, i think the billions of planet argument is only part of the story. There are other factors which need to be considered and which have unclear odds.
The building blocks of life may be common but as I understand it no-one knows the likelihood of life getting underway. It may be inevitable once you put the ingredients together, on the other hand it may be billions and billions to one.
Also, life appears to have drifted on quite happily for billions of years as single-celled organisms. At some point two cells thought two was better than one and multi-cellular life got going and led to dogs and cats and racoons and squirrels and everything else. Again, we don't know the odds of singled-cells organisms evolving. It could be inevitable given time, or the odds could be high.
Finally, intelligence evolved. That again could be inevitable or could be a freak event.
If the odds of life getting going, multi-celled creatures arriving and intelligence evolving are all very very high this may mean that we have few if any friends in the universe. If they are all low there should be some fascinating civilisations to meet.
Still, on past performance, if we meet any we'd probably try to put them in a zoo, hunt them or destroy them, so probably best if they stayed away.
Originally posted by legionnaireWouldn't it be cool if some vulcans came to us and said, live long and prosper?
This question is not directed at members of RHP, but a reference to what is known in astronomy as the Fermi paradox. This paradox, first posited by Enrico Fermi, (roughly) states that given that the lifespan of the universe is large (now known to be approximately 13 billion years) and that in a relatively short span of time (maybe 100 thousand years) hu ...[text shortened]... 's thoughts on this issue, and see which explanation people felt makes the most sense.
-mike
Olav
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Originally posted by legionnaireOur brains try and work out things form a human perspective, hence we create our gods in our own image and try to understand nature by our own rules of society.
This question is not directed at members of RHP, but a reference to what is known in astronomy as the Fermi paradox. This paradox, first posited by Enrico Fermi, (roughly) states that given that the lifespan of the universe is large (now known to be approximately 13 billion years) and that in a relatively short span of time (maybe 100 thousand years) hu ...[text shortened]... 's thoughts on this issue, and see which explanation people felt makes the most sense.
-mike
Maybe we do not see other life forms since they are from such a differnet form or construct that we simply do not perceive them, and likewise they may not perceive us, or simply choose not to.
If there is one thing that history teaches, it is that we as a race are very smug that we are right in our beliefs until someone comes along and total disproves the past othadoxy. There is a strong historical case that the way we perceive the universe now will seem very wrong in a couple of hundred years from now.
Andrew
Originally posted by kirksey957The idea that we are the only more or less intelligent life form in the entire universe seems a little silly to me.I mean,it's so enormous,so huge!How can we be the only ones?Unless,of course,we are freaks of the universe.Now that I think of it....that must be it!The universe screwed up and we appeared.Yes!
I may be arrogant. I may be stupid. But I'm afraid we're it. If I'm proven wrong, I'll be the first to say yes to the first two sentences. Kirk
And now the universe is stuck with us MWAAAAAAAHAHAHAHAHAHA 😛
Answer to this thread was posed in the form of an equation by
astronomer Frank Drake. The famous "Drake Equation" answers the
question "Where Is Everybody." I just copied this off the internet. Search for "Drake Formula Explain"
N = R* x fp x ne x f1 x fi x fc x L
R - Number of target stars in the galaxy that:
Are (1)second generation stars with heavy elements
(2) are hot enough to have a large habitable zone
(3)have a long enough lifetimes for life to develop
R = fp - Fraction (percentage) of those stars with planets or planet systems.
Fp = ne -Number of "Earth-like planets" in a planetary system that are at the right temperature for liquid water to exist (in the habitable zone).
Ne = fl - Fraction (percentage) of Earth-like planets where life actually develops
Fl = fi - Fraction (percentage) of Earth-like planets with at least one species of intelligent life
Fi = fc - Fraction (percentage) of Earth-like planets where the technology to communicate beyond their planet develops
Fc = L - "Lifetime" of communicating civilizations (years) - Note: This number must be divided by the age of the galaxy, 10 billion years, when you make your final calculation.
L = N - Number of communicative civilizations
___________________________________________
My remarks follow. As you can see, a lot of "unknowns" exist at this stage of our development. If you reverse the equation, and note that we have not (provably) made contact and not (provably) met any aliens, the inference can be made that we are a rather interesting species and earth is a good place to be from.
Concerning Fc... The latest estimates of the age of the universe is
13.7 billion years... See the WMAP , "Wilkinson Microwave Anisotropy Probe", studies done by the COBE , "Cosmic Background Microwave Explorer" guys. The 10 Billion year estimate for "our galaxie" might or might not be accurate. Depends entirely on the estimate from the big bang.
Mike
Originally posted by UncleAdamActually Adam... you might be getting "galaxies" mixed up with stars... but it might not matter. The inference of NASA's Hubble Deep Sky Image study leaves an estimate of about 50 Billion galaxies in our universe. That is 50,000,000,000 which is quite a stretch from the list if zero's in your post. but... We don't yet understand the laws of physics well enough to preclude your estimate, given that we might turn out to only one of "many" universes, and/or stuff we have not even thought of to question and test.
I'm sure there are extraterrestrial life forms on other planets somewhere because there are way more then 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,
000,0 ...[text shortened]... galaxys out there.
but as long as they dont try and invade us I dont mind them being there😉
Originally posted by CrowleySort of like not wanting to go near the foolish, brash six-year old holding the pointy stick? That's a depressing (although potentially realistic) thought.
What about another option.
There is ET life 'out there', they're peaceful, know about us, but are scared of OUR weapons?
...and Saddam Hussien 😛
Two points: Number one, Fermi's paradox appears to pertain only to other intelligent species within our own galaxy, since the distance between galaxies is enormous, and seems to be increasing, thus making inter-galactic travel much less likely than interstellar travel within a single galaxy (which seems unlikely in and of itself given relativisitic problems.)
Number two: It seems to me to be difficult, if not impossible, to infer anything from what has occurred on earth. Even though we have evolved intelligence, we have no idea if this is a common occurrence elsewhere, or the result of a miraculous convergence of fortuitious events here on earth. Therefore, it seems to leave a huge variatiability in the constants represented in Drake's equations - the number of intelligent civilizations could be 1 in every 5 planets with life, or 1 in every 5 million - with a single data point to work from, it's hard to extrapolate. Furthermore, we still as yet have no data showing the existence of any form of life at all outside of our own planet. So again, we don't know if even under the right conditions for our kind of carbon-based / water dependent life (of which our planet is the only known planet to have, besides maybe Europa) life will spontaneously form, or again if it requires really special conditions. Or maybe there are extremely prevalent silicon based life forms elsewhere. Who knows? Again, we have no idea. And each time there is a constant with a huge variability, the accuracy of the estimate coordinately decreases. So, until we start visiting other planets and get a better idea of what's out there we may be stuck with idle speculation.
-mike
Originally posted by legionnaireMike,
Number two: It seems to me to be difficult, if not impossible, to infer anything from what has occurred on earth. ... So, until we start visiting other planets and get a better idea of what's out there we may be stuck with idle speculation.
-mike[/b]
In one sense, i agree. The "details" of evolution preclude us (earthlings) as a model. We don't understand the "details" in fine grain form, so we should not use that form as a "given". But in a larger sense, i would maybe argue that our "model" here on earth... Type of Sun, Distance from Sun... etc. is a "proven model"... ie, we know that it worked here to generate "very abundant life and intelligent life in several species and 'Radio Capable' intelligence in a single species, Homo Sapiens". So as a purely imperical piece of data for Drakes equation, i think it would be ok to use "earth" as a "credible, viable" model as it applies to "planets in the right location to support liquid water. " The part we don't know yet is the "number of the beasts" that are out there in our galaxy. You are right in not wanting to use the "fine details" of our evolution, seeing as we don't yet even understand what happened that first billion years here on our planet. Was it a "jolt, a bolt and a moonshine still", or the "mighty finger of god" that stirred the kettle?
(being facetious actually... if "god" then where did it come from? "god" just adds a level of evolution and complexity to a situation that is in need of simplification, not extention.)
Mike
Originally posted by kirksey957No you are right.
I may be arrogant. I may be stupid. But I'm afraid we're it. If I'm proven wrong, I'll be the first to say yes to the first two sentences. Kirk
S.F. is it for them?
Let us look:
You think what is true and what is not:
1) You are alive.Who Gave you life?
2) You are independent of control.Who gave you this freedom that you enjoy?
You are in control of your life.Don't waste it.
Linda