Posted on 07/16/2018 10:04:54 AM PDT by PJ-Comix
t’s something people tell me all the time, and usually in hushed tones: “With a trillion planets out there, we really can’t be the only intelligent beings in the galaxy.” In other words, given the enormous amount of real estate in space, aliens are sure to exist. So why haven’t we found any?
I don’t dispute this straightforward idea because, after all, it underpins the search for extraterrestrial intelligence (SETI). But not everyone agrees. A recent paper by three researchers at the University of Oxford is throwing shade on those who feel confident that the cosmos is thick with extraterrestrials.
The Oxford academics were addressing a puzzle known as the Fermi Paradox, which describes the disconnect between our expectation of many worlds swarming with aliens and the fact that they remain undiscovered. Nearly 70 years ago, the celebrated physicist Enrico Fermi mouthed a deceptively simple question: “Where is everybody?” He made a quick estimate of how long it would take for any society bent on building an empire to colonize the entire Milky Way and realized it was only a few tens of millions of years, which is nearly 1,000 times shorter than the age of the galaxy.
This raised an obvious problem: There’s been more than enough time for aliens to spread out, and yet we don’t see them.
(Excerpt) Read more at nbcnews.com ...
Thanks for the quote which is not exactly the way I remembered hearing what he said. There's my problem, I never read his book. Maybe in the book he said that he expected to find said links now that he had written the theory.
It's not like one 'missing link' is missing - it's ALL of 'em. And yeah, enough time has gone by that we should have found some ...
So they came up with the "unlikely monster" theory which imagines fewer steps but larger steps. Therefore it is really hard to find the steps.
Well it simply had to be something other than creation so any wild theory will be faithfully believed without regard for proof. The believers are not even aware of the lack of proof.
” it would be logical that there is life in the galaxy.”
Logical? Based on what evidence?
Have you seen this response?
http://www.freerepublic.com/focus/f-religion/3670642/posts
LOL - you're right... zero awareness of any lack of proof ... It's why Darwin posited a possible explanation for the lack of proof...Now, all these years later we know the straw Darwin was grasping wasn't even real...
Would God let them meet and mingle with us? No. But it is possible they are watching us from a distance.
Or maybe they're too happy to be curious about the rest of the universe. I feel that way about most of the left and their problems. :)
According to Wikipedia:
Metallicity: In astronomy and physical cosmology, the metallicity or Z is the fraction of mass of a star or other kind of astronomical object that is not in hydrogen (X) or helium (Y). Most of the physical matter in the universe is in the form of hydrogen and helium, so astronomers use the word “metals” as a convenient short term for “all elements except hydrogen and helium”.”
The fundamental issue with metalicity is how long it takes for a star to be born that has sufficient metallicity.
Sufficient to what?
To have planets that aren't just big gas bags! To have so-called rocky worlds where life can develop.
Hear me out on this. Correct me where I am wrong, though! :)
It is theorized that the Big Bang occurred about 13 billion years ago. The farthest thing we can “reach” at the end or edge of the universe is the background noise of hydrogen, discovered by radio telescopes after WWII and it is estimated to be 13 billion light years away.
Immediately after the Big Bang, the universe existed as a dense cloud of hydrogen and empty space. There was no light. It took perhaps 200,000 years for enough hydrogen to coalesce and generate nuclear fusion. From this came the first stars.
But they were only hydrogen based, and as far as I know, nuclear fusion in a star is turning that hydrogen into helium.
How long these early stars lived I do not know, but according to Scientific America:
“The oldest galaxies and quasars that have been observed so far date from about a billion years after the big bang (assuming a present age for the universe of 12 billion to 14 billion years).”
I also read that the higher elements, that is, those beyond hydrogen and helium, are only created in a supernova, and among stars, supernovas are not an everyday thing, but only occur if that star is exceptionally massive.
So how long would this process of supernova after supernova have to take place in order for a star system to have enough rocky material to make a planetary system? Think of what this entails...
You need enough iron, aluminum, oxygen, nitrogen, silica, magnesium, sodium, chloride, sulfur, etc., etc. just to make a rock—or at least something that is not gaseous.
Now science says the Solar System (in which we live) has existed for the past 4 billion years, or when the universe was 9 billion years old. We can pretty much say it has all the elements necessary for life because life exists here. But there obviously has to exist some minimum level of metallicity to support life—or at least life as we know it. Even if some other forms life could exist, say silicon-based, it will need silica to exist, and that, like carbon, has to go thru the forge and fire of supernova to be created.
I’m not suggesting that the Solar System was the first system to have enough metallicity to create actual planets (and asteroids, comments, rocks, dust) but perhaps there isn't as many before us as we think.
My idea is that perhaps the universe has only had enough stars with metallicity for say 6 billion years or so.
Factor in all the other requirements for life, and then the requirements for intelligent life, and well, it could be far rarer than we assume, even given the vastness, age and amount of stars in the universe.
Perhaps life is exploding on all these other new (less than 6 billion years old) rocky worlds even now, but the elder civilizations just aren't out there.... YET.
I don’t think you’re thinking four dimensionally. If intelligent life is as plentiful as Sagan et al claim it is, then those millions of intelligent species just within our galaxy must necessarily be in varying levels of development. Therefore, there MUST be some of them who broadcasted EM signals a sufficient time in the past for them to reach us now. Instead? Silence. That silence speaks volumes.
With billions of galaxies out there, it is the height of arrogance to believe we are the only ones. If an advanced civilization can fold space or use/construct wormholes, all bets about time and distance are off the table. Just my two cents.
What do you say Doc?
Why stop at the galaxy? If life can’t start in the entire galaxy, then it won’t start in any other galaxy, either. Maybe the insipid grandiosity of ruling out any life but ours stands out too starkly when you say “universe.”
I find this 3000 year old bible verse very interesting. When God says there is nothing new under the sun it seems that He even means evolution which is just idolatry by any other name.
Jer 2:27 Saying to a stock, Thou art my father; and to a stone, Thou hast brought me forth: for they have turned their back unto me, and not their face: but in the time of their trouble they will say, Arise, and save us. (KJV)
Jer 2:27 Saying to a tree, ‘You are my father,’ And to a stone, ‘You gave birth to me.’ For they have turned their back to Me, and not their face. But in the time of their trouble They will say, ‘Arise and save us.’ (NKJV)
Rare earth is a plausible hypothesis. Maybe we really are alone. Or maybe faster than light travel is indeed an impossibility. If the latter, we would have to man a ship with Chicago Democratic voters to have any chance at all of reaching even a nearby star.
It could be for another, entirely different reason.
If you look at our history, from the development of radio communication to now, you'll see that our massive, high power broadcasting of radio signals into space has only been occurring for 125 years or so.
It is not only likely, but entirely probable that such radio signals will cease coming from our planet as we switch over to light based communications, and tightbands beamed source to source. The radio broadcast spectrum will continue to go down in power so that more spectrum can be used without interference. After all, if your signal can't be heard a mile away, someone a mile away can also use the same frequency.
If our societal use of high power broadcast signal lasts 200 years before we go dark, that is a VERY narrow cosmic time slice to catch a whiff of another society. It's entirely possible that 5 minutes before the first radio tower pointed towards the sky and turned on the receiver that the last broadcast signal of an alien civilization floated past our planet.
Finally, there is also the point that maybe a society doesn't WANT to be heard. Lights attract insects, maybe there are insects out there we don't want to attract.
Interesting. I have been pointing this out to folks for years.
You can’t just form a planet around a star, you have to have LOTS of extra elements other than hydrogen and Helium. And LOTS of time.
So, if we look at the night sky from a generally dark site, you can see about 2000 stars in an evening. Almost all that you can see are 1500 l.y. or less away from us (P Cygni is 6000 l.y. but very hard to see without a scope), most are less than 100 l.y. Almost all are WAY too young (even if they were second or third generation stars) to have had a chance to have life on any potential planets.
If it took 3.5 billion years for multi-cell life to form on the Earth, then why would a star only 500 million years old have a chance to produce anything, even simple life.
The Earth may be, indeed, a unique place.
Given the proximity of some recent UFO videos to the ocean, maybe we should be looking down instead of up.
Lord knows what could exist in the oceans or under the sea floor.
Well said.
“I’m religious and find it hard to imagine that God would create such an immense playground/laboratory, and not fill it with more creatures to entertain himself.”
God’s ways are not our ways. You are anthropomorphizing God, a heresy.
Although I tend to agree with you about only one planet being with life comporting with the Christian world-view, it is just my opinion. The Bible says God created man on this planet. It speaks not at all on what He may have done elsewhere.
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>> “ It speaks not at all on what He may have done elsewhere.” <<
Not so!
The Bible makes it clear in numerous ways that the purpose of creation is Man.
Why else would he destroy the entire physical universe when the last are gathered from Earth?
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Dunno.
Considering that, on Earth alone, we have three other sapient or near sapient species (dolphins and whales, great apes like chimps and gorillas, and octopi) I am not certain that sapient life is that rare.
Possible other reasons for them not being detected is that we just haven’t heard them yet (how long have we been listening vs. how long they have been putting out detectable signals and how far away they are), or that they’re deliberately being quiet. Or possibly, we’re not listening on the right frequencies.
A point. I’ll consider it, although I prefer direct statements from the Bible rather than inferences in interpretations. Not that I will disregard them.
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