The Fermi Paradox

[Steve DeRosa]

Originally Posted by rllink

I've been to Roswell, I know things you can't imagine. And I have a tee shirt.

Guess I'm lucky being a lifelong New Yorker - I can get all that in Times Square, just a ferry/subway ride away...

[DCCougar]

Originally Posted by robj144

The good thing about spacetime is that it's "malleable" according to General Relativity. Hypothetically, if our species survives another few hundred years, I'm fairly certain we'll have the energy and resources to bend spacetime....

Yeah, space is "malleable," but it's "matter that tells space-time how to curve." It takes a black hole to do some serious curving. "Bending space" is a great sci-fi device, but as an interstellar "vehicle," I doubt there's any way for that to be happening.

The problem with the Fermi paradox is that intelligent life that proceeds to control electromagnetism (and thus radio, etc.) is much more rare than simple extraterrestrial life. Earth had "intelligent life" for maybe a billion years (animals), but humans only got into radio in the last few hundred years. That's, like, nothing! Other animal species lived for millions of years and obviously never got into what humans have gotten into. And of course, evolution is pretty haphazard. What if a giant asteroid (comet?) had never wiped out the dinosaurs? Nothing says any other planet has to evolve like ours did. In fact, you can be sure they won't.

Then there's the issue of the lightyear. It's just so darn far! And we're talking about hundreds, thousands, hundreds of thousands of lightyears just in our single galaxy. If you want to start invoking the statistical possibilities of the billions of other galaxies, you're talking about distances that are pretty well beyond imagination.

I think the most we can hope for is a signal from out there, which has been traveling at light speed. But signal strength drops off with the square of the distance. It would have to be really strong at its emission, and our detectors would have to be super sensitive. We're getting fairly good with the latter, but.....

[Dru Edwards]

Originally Posted by Aimelie

Hi Dru!

And I’m pretty sure you know a lot more about this subject than you initially let on. Cool cat that you are…

Hi Aimelie! I've read a lot about the Fermi Paradox and it's interesting. Great comments and feedback in this thread from AGF'ers. We have people who are knowledgeable in astronomy and can offer informative opinions.

As much as I want to see it, I don't think we'll see First Contact in our lifetime, perhaps ever.

[Dirk Hofman]

Originally Posted by rokdog49

I have it on very good authority there is no intelligent life anywhere beyond this planet.

In the entire universe? That's amazing, good to know! I can rest easy now that it's all settled. I'm honestly a bit disappointed, but it's probably for the best.

Do you know if there ever has been or ever will be? Since you seem to be in the know...

[Slothead56]

I have avoided this thread because a) I don’t know squat about astronomy; b) I am pretty much unread on all things space related (tho’ I do love Apollo 13); and c) thinking about this stuff makes my brain hurt.

Having said all that, I think any Earthling would be pretty arrogant to think we are ‘it’. The Milky Way a 100,000 light years across and we’re the only intelligent life? Good lord….we may be the least intelligent life!

[robj144]

Originally Posted by DCCougar

Yeah, space is "malleable," but it's "matter that tells space-time how to curve." It takes a black hole to do some serious curving. "Bending space" is a great sci-fi device, but as an interstellar "vehicle," I doubt there's any way for that to be happening.

The problem with the Fermi paradox is that intelligent life that proceeds to control electromagnetism (and thus radio, etc.) is much more rare than simple extraterrestrial life. Earth had "intelligent life" for maybe a billion years (animals), but humans only got into radio in the last few hundred years. That's, like, nothing! Other animal species lived for millions of years and obviously never got into what humans have gotten into. And of course, evolution is pretty haphazard. What if a giant asteroid (comet?) had never wiped out the dinosaurs? Nothing says any other planet has to evolve like ours did. In fact, you can be sure they won't.

Then there's the issue of the lightyear. It's just so darn far! And we're talking about hundreds, thousands, hundreds of thousands of lightyears just in our single galaxy. If you want to start invoking the statistical possibilities of the billions of other galaxies, you're talking about distances that are pretty well beyond imagination.

I think the most we can hope for is a signal from out there, which has been traveling at light speed. But signal strength drops off with the square of the distance. It would have to be really strong at its emission, and our detectors would have to be super sensitive. We're getting fairly good with the latter, but.....

Don't discount technology. If you would have told someone just 150 years we landed on the moon and sent robots to Mars, they would have said you're crazy and told you that was impossible:

https://www.popularmechanics.com/sci...ve-space-time/

[Methos1979]

Interesting thread. I'm not sure if it's my advancing age but the optimism of my youth has rapidly accelerated into the pessimism of age and I'm convinced that the human race is too flawed to ever be able to work together in harmony long enough to do much other than fling a few unmanned vehicles into space to see what's out there. I'm quite sure that if any of them encounter anything of note, we'll be long gone.

Our ability to advance our technology has fast outpaced our ability to advance socially and intellectually leading to what one can only conclude will be our self-destruction. Civilizations ascend and decline. This one is in decline and will self-destruct very soon resetting the human clock once again. Now, if you'll excuse me, I'm going to head over to the classifieds to buy a really cool guitar before it's too late!

[seannx]

Very interesting discussion…
Not being familiar with the Drake Equation, I did a google search, and found this on Wikipedia…

A civilization lasting for tens of millions of years could be able to spread throughout the galaxy, even at the slow speeds foreseeable with our own current technology. However, no confirmed signs of civilizations or intelligent life elsewhere have been found, either in our Galaxy or in the observable universe of 2 trillion galaxies.[77][78] According to this line of thinking, the tendency to fill up (or at least explore) all available territory seems to be a universal trait of living things, so the Earth should have already been colonized, or at least visited, but no evidence of this exists. Hence Fermi's question "Where is everybody?".[79][80]

A large number of explanations have been proposed to explain this lack of contact; a book published in 2015 elaborated on 75 different explanations.[81] In terms of the Drake Equation, the explanations can be divided into three classes:

Few intelligent civilizations ever arise. This is an argument that at least one of the first few terms, R∗ · fp · ne · fl · fi, has a low value. The most common suspect is fi, but explanations such as the rare Earth hypothesis argue that ne is the small term.
Intelligent civilizations exist, but we see no evidence, meaning fc is small. Typical arguments include that civilizations are too far apart, it is too expensive to spread throughout the galaxy, civilizations broadcast signals for only a brief period of time, communication is dangerous, and many others.
The lifetime of intelligent, communicative civilizations is short, meaning the value of L is small. Drake suggested that a large number of extraterrestrial civilizations would form, and he further speculated that the lack of evidence of such civilizations may be because technological civilizations tend to disappear rather quickly. Typical explanations include it is the nature of intelligent life to destroy itself, it is the nature of intelligent life to destroy others, they tend to be destroyed by natural events, and others.
These lines of reasoning lead to the Great Filter hypothesis,[82] which states that since there are no observed extraterrestrial civilizations despite the vast number of stars, at least one step in the process must be acting as a filter to reduce the final value. According to this view, either it is very difficult for intelligent life to arise, or the lifetime of technologically advanced civilizations, or the period of time they reveal their existence must be relatively short.

An analysis by Anders Sandberg, Eric Drexler and Toby Ord suggests "a substantial ex ante probability of there being no other intelligent life in our observable universe".[83]

Here’s the link to the article: https://en.wikipedia.org/wiki/Drake_equation

[roberts]

So....What do you make of UFO sightings. I always felt that if ET life were to visit Earth it would not take a form that mimics our understanding of life, e.g. riding in vehicles with propulsion, shapes within our geometric understanding, and lights. But yet the sightings are pretty cool and mysterious. How does all this fit into the paradox...?

[Dirk Hofman]

Originally Posted by roberts

So....What do you make of UFO sightings. I always felt that if ET life were to visit Earth it would not take a form that mimics our understanding of life, e.g. riding in vehicles with propulsion, shapes within our geometric understanding, and lights. But yet the sightings are pretty cool and mysterious. How does all this fit into the paradox...?

Well they are by definition "unidentified", so who knows? Maybe they're us. Time Travel tourists from the distant future?

[H165]

I don't think we'll ever get there, at least not with a person onboard.

Technology advances quickly. I have faith in it. I think we'll get there.

I graduated high school 54 years ago. If our valedectorian had correctly predicted that some of us would be sitting in front of a typewriter attached to a television, which was then hooked up to a worldwide audio/video/media network, bidding against others located worldwide in a live auction for the privelege of paying $100 for an electric toothbrush, she'd have been laughed off the podium. It wasn't just the problem that the technology didn't exist, it was that the idea of the technology only existed in fiction.

Our kids know their parents' science fiction as existing facts. Let's hope the kids in later generations can do the same.

"a substantial ex ante probability of there being no other intelligent life in our observable universe".[83]

The key word here is "observable". Our current capability to "observe" is about level 1 out of 1,000, which makes the above conclusion valid, but also insignificant.

This is a fun forum

[roberts]

Originally Posted by Dirk Hofman

Well they are by definition "unidentified", so who knows? Maybe they're us. Time Travel tourists from the distant future?

Traveling in time is harder for me to comprehend than traveling far. What is the scientific probability for time travel - beyond Rod Taylor and Yvette Mimieux....

[Dirk Hofman]

Originally Posted by roberts

Traveling in time is harder for me to comprehend than traveling far. What is the scientific probability for time travel - beyond Rod Taylor and Yvette Mimieux....

Maybe a solution for either long distance or time is connected. Spacetime and all that...

Well beyond my ability to comprehend!

[Aimelie]

Originally Posted by seannx

Very interesting discussion…
Not being familiar with the Drake Equation, I did a google search, and found this on Wikipedia…



Here’s the link to the article: https://en.wikipedia.org/wiki/Drake_equation

Great post! Depressing—but great.

[DCCougar]

Originally Posted by robj144

Don't discount technology. If you would have told someone just 150 years we landed on the moon and sent robots to Mars, they would have said you're crazy and told you that was impossible:

Oh, I hear you. Just 100 years ago we were first realizing (with evidence) that ours was not the only galaxy in the Universe. Since then the advance of science has been astounding. Now we know there are billions upon billions of galaxies. (We still have no clue about dark energy, not to mention dark matter.) But for "folding space," the problem is physics. It takes a huge amount of mass to bend space in any significant amount. Gravitational lenses bend passing light from super distant, bright objects, but the "lens" is an entire galaxy with billions of solar masses.

Technology may enable us to get going really fast through space, but there's a lot of gas and dust and other debris out there, so shielding is going to be a major problem for any spacecraft. Technology may also solve that problem, but then there's the ridiculous distances involved....