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Astrophysicist Believes Technologically-Advanced Species Extinguish Themselves (sciencedaily.com)
Why haven't we heard from intelligent life elsewhere in the universe? wisebabo writes:
In the Science Daily article "Where is everybody? The Implications of Cosmic Silence," the retired astrophysicist Daniel Whitmire explains that using the principle of mediocracy (a statistical notion that says, in the absence of more data, that your one data point is likely to be "average"), that not only are we the first intelligent life on earth but that we will likely be the only (and thus the last) intelligent life on this planet... Unfortunately that isn't the worst of it.
Coupled with the "Great Silence", it implies that the reason we haven't heard from anyone is that intelligent life, when it happens anywhere else in the universe, doesn't last and when it does it flames out quickly and takes the biosphere with it (preventing any other intelligent life from reappearing. Sorry dolphins!). While this is depressing in a very deep sense both cosmically (no Star Trek/Wars/Valerian universes filled with alien civilizations) and locally (we're going to wipe ourselves out, and soon) it is perhaps understandable given our current progress towards reproducing the conditions of the greatest extinction event in earth's history.
That last link (reprinting a New York Times opinion piece) cites the "Great Dying" of 90% of all land-based life in 252 million B.C., which is believed to have been triggered by "gigantic emissions of carbon dioxide from volcanoes that erupted across a vast swath of Siberia." But if we're not headed to the same inexorable doom, that raises an inevitable follow-up question.
If intelligence-driven extinction doesn't explain this great cosmic silence, then what does? Why hasn't our species heard from other intelligent civilizations elsewhere in the universe?
Coupled with the "Great Silence", it implies that the reason we haven't heard from anyone is that intelligent life, when it happens anywhere else in the universe, doesn't last and when it does it flames out quickly and takes the biosphere with it (preventing any other intelligent life from reappearing. Sorry dolphins!). While this is depressing in a very deep sense both cosmically (no Star Trek/Wars/Valerian universes filled with alien civilizations) and locally (we're going to wipe ourselves out, and soon) it is perhaps understandable given our current progress towards reproducing the conditions of the greatest extinction event in earth's history.
That last link (reprinting a New York Times opinion piece) cites the "Great Dying" of 90% of all land-based life in 252 million B.C., which is believed to have been triggered by "gigantic emissions of carbon dioxide from volcanoes that erupted across a vast swath of Siberia." But if we're not headed to the same inexorable doom, that raises an inevitable follow-up question.
If intelligence-driven extinction doesn't explain this great cosmic silence, then what does? Why hasn't our species heard from other intelligent civilizations elsewhere in the universe?
hahaha humans are intelligent. We're everything intelligence shouldn't be, aliens know this and avoid us. nothing to see here.
The universe is just too big to hear anyone else.
Standing on the shore in Spain you couldn't hear anyone shouting from Hispaniola, yet when Columbus landed there he found loads of people. Space is a hell of a lot bigger than the Atlantic Ocean and relatively any radio signal we can send is quieter than the man screaming on the beach in our example. So quit it with the all life will destroy itself pessimism.
Not only is space incomprehensibly vast, but so is time. 16 billion years sounds easy to say, but if an intelligent species only broadcasts "clear", identifiable uncompressed unencrypted radio for ~100 years, then we have only 1 in 160 million chances of finding them with something like SETI.
They just aren't there! Why can't people of science accept this?
It's sometimes called the Rare Earth Hypothesis but KS Robinson really explains it well in his Mars Trilogy books.
Basically the theory goes that lower level life may or may not be 'common' in the universe, but intelligent life is so rare that given distances and the speed of light and whatnot we just probably won't ever encounter each other.
It's elegant and explains everything and should be the accepted theory in exobiology (if it isn't already) until evidence proves otherwise.
Thank you Dave Raggett
For all we know, the universe is all chatting with each other via quantum entanglement or something even more advanced, and we're off in the corner thwacking our electromagnetic equipment on the side saying, "Is this thing on? Where is everybody?"
Nuclear war is very messy, but won't exterminate life. Especially human life.
Survival is tough and ugly. Violence didn't start with humans, not by a long shot. Species have been killing each other since the beginning of life on earth.
I suspect that if there is life elsewhere, survival is just as hard for those life forms, leading to just as much violence.
Our technology is to the point where we could prevent a recurrence of the Great Dying. All you have to do is unshackle your mind from the popular notion that the only solution to CO2 emissions is passive (reducing emissions via renewable energy sources).
CO2 (and water) are popular end-products for exothermic chemical processes (e.g. burning gasoline, cellular respiration) because it sits at an extremely low energy potential. That is, chemical processes which result in CO2 give off a lot of energy. To reverse the process, you have to put a lot of energy into the CO2 to break apart the carbon and oxygen atoms.
If you have sufficient energy, you can actively drive that reverse process. Plants do it via photosynthesis, driving it with energy from sunlight. We could do it with nuclear power - generating massive quantities of electricity (more than can reasonably be obtained from solar, wind, hydro) to decompose CO2. Generating sufficient power to offset volcanic emissions of CO2 would be incredibly expensive, but given the alternative (extinction) we're technologically capable of doing it.
The same is true if this push for renewables as the only solution to global warming fails. If renewables can't be developed quickly enough to supplant fossil fuel energy sources and CO2 levels continue to rise, at some point we concede that renewables aren't arresting CO2 levels quickly enough. Then we'll be forced to switch to nuclear power to buy ourselves more time. This is why shuttering operational nuclear plants as Germany is doing is extremely short-sighted. Nuclear is our ultimate trump card. We want to keep it ready in our back pocket as a hedge in case renewable energy can't be rolled out quickly enough.
But we don't really understand why WE developed intelligent life.
Why didn't the dinosaurs? There could have been intelligent life (in the sense of tool use, construction etc.) a quarter billion years ago, but as far as we can tell there wasn't. There was only semi-intelligent life (in the sense of mobility, family structures etc. compared to plant and microbe life, ie. animals).
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Or, maybe those mega-structures aren't really feasible -- and if they are, they aren't practical or economical. Maybe most life evolves around brown dwarf stars that won't burn out 'til near the end of the universe, and so the life on planets around those stars sees no reason to ever leave the nest. They have everything they need and decide to keep to themselves.
Maybe there's life everywhere, but their communications are point-to-point lasers or some other method we just can't detect.
Spreading life from one star system to another at sub-light speeds would mean generational ships, cryostasis, robots, and/or artificial wombs for incubating frozen zygotes. Maybe it's just not worth it for other civilizations to even bother -- at least until their sun is about to go nova... and even then, it's a huge, possibly enormously expensive risk, and politically... who gets to get on that life boat exactly? Maybe their philosophy, politics, or religion would prevent them from abandoning their dying world.
The fact is -- we really don't know what we're looking for and haven't been listening for long enough to have any idea of what we may have missed. Surely civilizations rise and fall without us ever knowing. We've only been broadcasting ourselves for the past couple centuries out of the 4-5 billion years life has been on our planet. There's always the possibility that we are the first civilization in our corner of our galaxy (someone had to be first!). But there's billions of galaxies... and we can barely detect things in a small radius from our location in our own galaxy.
We really don't have any data to work with. It'd be nice if we'd start sending probes to nearby star systems so that in a few thousand years, we'd know if any of them harbored life of some sort.
Unfortunately, the gas producing establishment is too strong to push this solution
Uh...it would also cost several trillion dollars to do it on a sufficient scale to reverse climate change before it's pretty disastrous. That just might be a factor in this approach.
You need an absurd number of carbon-capture-factories built in a couple decades. That's not cheap.