Go Back   Freethought Forum > The Marketplace > The Sciences

View Poll Results: Are we alone in the Universe, based on the evidence at hand?
We are almost certainly alone. 1 6.67%
We are probably alone. 2 13.33%
We are probably not alone. 11 73.33%
We are definitely NOT alone. 2 13.33%
All the life is Planet X 3 20.00%
Multiple Choice Poll. Voters: 15. You may not vote on this poll

Reply
 
Thread Tools Display Modes
  #1  
Old 06-18-2019, 01:53 AM
Kyuss Apollo's Avatar
Kyuss Apollo Kyuss Apollo is offline
happy now, Mussolini?
 
Join Date: May 2006
Location: location, location
Posts: VDCCXXIII
Blog Entries: 7
Images: 17
Default A Sample of...One

I read Peter Ward's and Donald E. Brownlee's book, Rare Earth, about twenty years ago, after watching a documentary where Ward and Brownlee explained the Rare Earth Hypothesis, that "that the origin of life and the evolution of biological complexity such as sexually reproducing, multicellular organisms on Earth (and, subsequently, human intelligence) required an improbable combination of astrophysical and geological events and circumstances."

Having been raised on sci-fi (and a scientific community) making the opposite assumption -- that the universe is teaming with life and civilizations in various stages of development -- consideration of this notion was as profound to me as the realization that there is (almost) certainly no afterlife or a universal entity. I'd like to imagine that there is life on Mars, and that someday we'll encounter Vulcans and Romulans, but if we don't destroy ourselves in the meanwhile the makeup of such a civilization is more likely to resemble Isaac Asimov's Galactic Empire than Gene Roddenberry's Federation of Planets.

I was reminded of this after watching David Kipping's recent video (posted below), in turn based on "On the Rate of Abiogenesis from a Bayesian Informatics Perspective" an article he co-authored published last year in Astrobiology. That to answer the Drake Equation with any number higher than one, is an act of faith, with no real statistical or scientific basis in fact.
__________________
This week's track: Earthlesss - Godspeed




Reply With Quote
Thanks, from:
Ari (06-18-2019), But (06-18-2019), ChuckF (06-20-2019), Crumb (06-18-2019), Ensign Steve (06-18-2019), JoeP (06-18-2019), Kamilah Hauptmann (06-18-2019), Stormlight (06-20-2019)
  #2  
Old 06-18-2019, 01:58 AM
Kyuss Apollo's Avatar
Kyuss Apollo Kyuss Apollo is offline
happy now, Mussolini?
 
Join Date: May 2006
Location: location, location
Posts: VDCCXXIII
Blog Entries: 7
Images: 17
Default Re: A Sample of...One

__________________
This week's track: Earthlesss - Godspeed




Reply With Quote
Thanks, from:
Stormlight (06-20-2019)
  #3  
Old 06-18-2019, 12:14 PM
JoeP's Avatar
JoeP JoeP is offline
YELLOW HAIR FAKE ANIMAL
 
Join Date: Jul 2004
Location: England/Miisaland
Gender: Male
Posts: XXVMCMLXXXVII
Images: 18
Default Re: A Sample of...One

We're not alone but we might as well be: we can't even define life very well and we certainly can't define intelligence. All these assumptions we tend to make about prerequisites for life are unjustified: carbon-based, liquid water-based, even planet-based. And the assumptions we make about intelligence are unjustified: must arise from living things or be created by living things; probably motivated by reproduction; probably motivated to communicate.

The universe is probably full of things that have things in common with life as we know it, but (a) we will never discover the vast majority of them and (b) when we do, our definition of life will be challenged. And the universe is probably full of things that have things in common with intelligence as we think we define it, but we will never encounter most of them because they don't communicate or leave signs that we have any chance of recognising, and the ones we do encounter will challenge our definition of intelligence (just as each advance in AI does - "OK, that may be part of something intelligent beings can do but not the whole thing").

If we last long enough to get any actual observations, rather than just the current speculation, I predict the universe we know will end up being a (messy) continuum between lots of processes that definitely aren't life to things that most of us agree are alive, and a (messier) continuum between things that are completely dumb and entities that most of us agree have some fundamental qualities of intelligence.

And even if we survive as humans (possibly augmented and/or virtualised) for a million years and explore the whole galaxy, that's still a tiny tiny fraction of the universe - and what we experience will be a tiny fraction of what is going on in the galaxy under our noses.
__________________

:roadrun:
Free thought! Please take one!

:unitedkingdom:   :southafrica:   :unitedkingdom::finland:       :eur:       :m&ms::m&ms::twix::twix: (rotated 180°):m&ms::m&ms:
Reply With Quote
Thanks, from:
Ari (06-18-2019), ChuckF (06-20-2019), chunksmediocrites (07-01-2019), Crumb (06-18-2019), Ensign Steve (06-20-2019), Kyuss Apollo (06-18-2019), Qingdai (06-28-2019), Sock Puppet (06-18-2019), SR71 (06-18-2019), Stormlight (06-20-2019)
  #4  
Old 06-18-2019, 05:43 PM
Sock Puppet's Avatar
Sock Puppet Sock Puppet is offline
Turkey Soviet agent, ominous or flat-bottomed
 
Join Date: Oct 2005
Location: Down by the Bay
Posts: XMMMCMI
Blog Entries: 7
Images: 120
Default Re: A Sample of...One

What Jope said - particularly "We're [I would add probably] not alone but we might as well be." Regardless of how long we survive as a species, even in the best case, I don't think we primates will ever get a large enough sample to find and recognize other intelligences, no matter how powerful our thinking-machines get. Perhaps our thinking-machines and someone else's could eventually exchange information, but it would be over distances and time periods that might as well be meaningless to us.
__________________
:sockpuppet:...........
Reply With Quote
Thanks, from:
Ari (06-18-2019), ChuckF (06-20-2019), chunksmediocrites (07-01-2019), JoeP (06-18-2019), Kyuss Apollo (06-18-2019), SR71 (06-18-2019), Stormlight (06-20-2019)
  #5  
Old 06-18-2019, 07:22 PM
The Lone Ranger's Avatar
The Lone Ranger The Lone Ranger is offline
Jin, Gi, Rei, Ko, Chi, Shin, Tei
 
Join Date: Jul 2004
Posts: MXDX
Images: 523
Default Re: A Sample of...One

I've always found the Rare Earth Hypothesis ... not entirely convincing.

First, as we now know, planets are actually quite common. As such, there should be lots of planets out there that happen to inhabit the "Goldilocks zones" around their respective stars.

Second, though there's a lot we don't know about how life arose on this planet, what we do know is that organic molecules form surprisingly rapidly and easily under conditions similar to those that prevailed early in the Earth's history. It doesn't seem unlikely that there are hundreds, maybe thousands, perhaps even millions of planets in our galaxy alone where life as we'd understand it arose.


But here's the rub: how likely is it that there's life out there that we could a.) recognize, and b.) communicate with? The answer is: not very likely at all.

After all, if we define "intelligent life" as life that produces signals or probes that we could detect, then "intelligent life" has arisen only once in the roughly 4 billion-year history of life on Earth. There is nothing to suggest that there's anything at all inevitable about the evolution of an "intelligent," technological species.

And even if hundreds -- heck, even thousands -- of such species have evolved in our galaxy, given the vast distances involved and the limitations imposed by the finite speed of light, the chances that any of them would happen to coexist and be close-enough for any sort of communication between them are virtually zero.


So, in short: Is Earth the only planet in the galaxy (much less the Universe) that supports life as we'd recognize it? Almost certainly not. Are we ever going to encounter and communicate with an alien civilization? Almost certainly not.


Such is my estimation, anyway. I'd love it if Star Trek turned out to be correct and the galaxy is teeming with intelligent life -- but that seems very unlikely, to put it mildly.


Peter Mulvey sums it up nicely:

__________________
“The greatest way to live with honor in this world is to be what we pretend to be.”
-- Socrates
Reply With Quote
Thanks, from:
Ari (06-18-2019), But (06-18-2019), ceptimus (06-19-2019), chunksmediocrites (07-01-2019), Crumb (06-18-2019), Kyuss Apollo (06-19-2019), Limoncello (06-18-2019), Megatron (06-20-2019), specious_reasons (06-19-2019), SR71 (06-18-2019), Stormlight (06-20-2019)
  #6  
Old 06-18-2019, 07:46 PM
Limoncello's Avatar
Limoncello Limoncello is offline
ChuckF's sock
 
Join Date: Dec 2016
Gender: Female
Posts: MMDCCLXXX
Images: 5
Default Re: A Sample of...One

:ufo:
Attached Images
File Type: jpg 64575600_10161848920690015_7691959739038564352_n.jpg (23.3 KB, 3 views)
__________________
#jeSuisLimoncello


:lemon:..
Reply With Quote
Thanks, from:
chunksmediocrites (07-01-2019), Crumb (06-18-2019), JoeP (06-18-2019), Kyuss Apollo (06-19-2019), SR71 (06-21-2019), Stormlight (06-20-2019), The Lone Ranger (06-18-2019)
  #7  
Old 06-18-2019, 08:42 PM
But's Avatar
But But is offline
This is the title that appears beneath your name on your posts.
 
Join Date: Jun 2005
Gender: Male
Posts: MVDCCLXIV
Default Re: A Sample of...One

Quote:
Originally Posted by The Lone Ranger View Post
I've always found the Rare Earth Hypothesis ... not entirely convincing.

First, as we now know, planets are actually quite common. As such, there should be lots of planets out there that happen to inhabit the "Goldilocks zones" around their respective stars.

Second, though there's a lot we don't know about how life arose on this planet, what we do know is that organic molecules form surprisingly rapidly and easily under conditions similar to those that prevailed early in the Earth's history. It doesn't seem unlikely that there are hundreds, maybe thousands, perhaps even millions of planets in our galaxy alone where life as we'd understand it arose.

Another big discovery that changes the whole picture is that you don't have to be anywhere near a "habitable zone" to have things like massive, stable salt water oceans that may outlive their parent stars by billions of years.
Reply With Quote
Thanks, from:
ceptimus (06-19-2019), chunksmediocrites (07-01-2019), Limoncello (06-19-2019), SR71 (06-21-2019), Stormlight (06-20-2019), The Lone Ranger (06-19-2019)
  #8  
Old 06-18-2019, 07:14 PM
Ari's Avatar
Ari Ari is offline
I read some of your foolish scree, then just skimmed the rest.
 
Join Date: Jan 2005
Location: Bay Area
Gender: Male
Posts: MXCMLII
Blog Entries: 8
Default Re: A Sample of...One

IMO the drake equation hand waves away a number of serious issues.

One is the true vastness of the universe. Sure I’ve seen workings out of how probes could ‘visit’ every star in our galaxy in under a million years and since time is also vast it should have obviously happened at least once, but it still misses the vastness of space. Space is so vast that multiple space exploring probe networks could be roaming our galaxy right now and not know about each other, let alone know about us or be obvious enough we know about them. Space is so vast that when the andromeda galaxy and the milkyway collide it’s likely none of the stars in the arms collide and that only the most massive of the black holes in the cores will capture each other or have a good chance of hitting, because space is vast and mostly empty. Shows like Star Trek are great but have skewed our perception of space as smaller than it is, with stars just wizzing by even at low warp, though in reality a still photo is good enough to represent light speed travel to our nearest star for at least the first few months of the journey.

Which comes back to exploration and being stuck in a conserved universe. Due to the energy required to change speeds the probes will either move fast and zip on by, or slowly get up to speed then use energy carried with them to slow down again to the glacier pace needed to enter the planetary orbit of a star. I would prosume the best version is a combination of fast moving probes that send back signals to the slow probes to stop at stars of interest. In the end the exploring civilization gets a rolling snapshot of the galaxy with choice areas in enough detail to see life, but not some sort of omnipotent and always updated view. For any non-galactic-scale-god-like civilization it would take an active and on going interest over potentially millions of years to get a full detailed survey of everything in our galaxy in a manner that would then allow them to time signals or probes to thread the needles needed to make real first contact.

Another is the presumption there’s any use in space travel. Once a civilization has colonized a few planets and mined a bunch of asteroids providing ample resource breathing room what really is the use in exploring interstellar space? While there are probably plenty of good reasons, we are now down to guessing the psyche of space civilizations and I don’t even know where to start. The drake equation is fine for naturally driven probabilities like the chance of water or of self replicating chemicals, but when it comes to actual contact we are trying to quantify an alien intelligence’s interest in exploring vast empty and harsh spacetime in a way that either makes contact or spews enough waste that it’s obvious they’re there. How do we quantify the likelihood that an alien species won’t get bored of space exploration after the thrill of visiting other planets in their solar system has worn off?

Which leads to my opinion as a likely answer, that many alien civilizations eventually discover the ability to fabricate reality as they sense it and either through biomechanical interfaces or through just being an artificial intelligence created by or in mimic of their species, encountering strange looking life from odd lands, but all in a simulated environment.
Reply With Quote
Thanks, from:
But (06-18-2019), ceptimus (06-19-2019), chunksmediocrites (07-01-2019), Crumb (06-18-2019), JoeP (06-18-2019), Kyuss Apollo (06-19-2019), Sock Puppet (06-18-2019), Stormlight (06-20-2019), The Lone Ranger (06-18-2019)
  #9  
Old 06-18-2019, 09:39 PM
erimir's Avatar
erimir erimir is offline
Projecting my phallogos with long, hard diction
 
Join Date: Sep 2005
Location: Dee Cee
Gender: Male
Posts: XMMMCCXXVI
Images: 11
Default Re: A Sample of...One

I think there's "life" out there, in the sense of self-replicating information-carrying structures (like DNA or RNA but potentially different).

Of course, microbes are much more likely than macroorganisms (given Earth's history of life and their relative prevalence). And vegetative macroorganisms are probably much more likely than animal-like ones. And dumb alien animals are more likely than intelligent ones. And so on, with intelligent enough to communicate less likely, intelligent enough to develop complex technology, intra-solar-system space travel, interstellar travel, intergalactic travel, etc. etc.

For intelligent life also needs to have managed not to destroy itself, and given human history, it seems like developing a general intelligence can be such a strong adaptive advantage (the ability to outsmart disease, exploit non-obvious resources, develop weapons that aid in hunting and largely eliminate the threat of predators, etc.) that it leads to population growth that will consume the planet's resources and create conflict, etc. long before they develop the means for interstellar travel and colonization. The idea of Vulcans is nice, but given what we know about evolution, doesn't it seem only logical that the illogical and selfish Vulcan ancestors might've reproduced more? It could be that technological civilizations tend not to survive very long. It could be that there have been thousands or millions of advanced (i.e. to human level technology) civilizations in the universe... and also that >99% of them are long gone.

And given that a planet has life, it isn't guaranteed to be easily discoverable. Evolution is powerful but there are still areas of Earth that are devoid of life. It could be that it's on a planet with a frozen surface and the life is in the oceans beneath. Or it could be that the life is deep down where there is geothermal heat. It could be that life once covered the planet, but massive changes to the planet, climate changes or asteroid strikes or the like have killed most of it. Maybe eventually the remaining/existing life will adapt to colonize the rest of the planet, but that could be millions and millions of years from now.

It's also possible there could be lifeforms we wouldn't even recognize as life (at least, not for a long time) even if they fell into our laps.

But how likely is it to be near enough to us that we can discover it directly? Given how much effort it has been to explore our own backyard... While unlikely, it could be there are or were microbes on Mars but we haven't even explored the areas of Mars with significant amounts of water. But imagine that there are microbes on a planet in one of the 1,000 closest solar systems (all of which are light-years from ours!) - which would already be a pretty lucky occurrence. How long would it take us to explore those solar systems, to be able to travel to the planet, and to discover the existence of microbes on the surface? And then think of how much rarer life intelligent enough to have developed language and civilization would be.

I think the possibility of some sort of life, and even intelligent life, elsewhere in the universe is pretty high. Especially if we also allow that it could've existed in the past but be dead now. But the likelihood we'll ever encounter any of it, much less advanced spacefaring civilizations that we would want to meet (because given human history of uncontacted peoples, being contacted seems highly likely to be disastrous* even if the aliens don't just immediately declare war on us), seems extremely low to nonexistent.

*On the other hand, one could propose that species that behave in a warlike/oppressively colonial manner would be less likely to develop to the point of being able to visit Earth, since they may be more likely to destroy themselves through infighting and resource mismanagement. In other words, the Klingons would've been too busy nuking each other to get to the point where they could make contact with humans, while the Vulcans wouldn't. On the other other hand, it could also be that they would be a species that's developed a more eusocial way of being and their high-level of intraspecies peacefulness has little to no bearing on how they'd treat humans. And on the fourth hand, organisms vary! Even if the Vulcans as a whole were peaceful on planet Vulcan in the period immediately preceding their development of easy interstellar travel, there's no guarantee that Vulcan colonists would be so or remain so since the survival pressures would be very different and it would probably be a very non-representative sample of Vulcans who would choose to leave the homeworld.
Reply With Quote
Thanks, from:
Ari (06-18-2019), ceptimus (06-19-2019), ChuckF (06-19-2019), JoeP (06-18-2019), Kyuss Apollo (06-19-2019), Limoncello (06-19-2019), SR71 (06-21-2019), Stormlight (06-20-2019), The Lone Ranger (06-19-2019)
  #10  
Old 06-19-2019, 11:07 AM
ceptimus's Avatar
ceptimus ceptimus is offline
puzzler
 
Join Date: Aug 2004
Location: UK
Posts: XVDCCCLXXVI
Images: 28
Default Re: A Sample of...One

There are thought to be a few peculiar things about Earth, and the solar system, that make the Earth likely to be unusual in the length of time it has sustained a liquid water environment:

1. Jupiter is thought to have entered into an unlikely resonance lock with Saturn early in the solar system's evolution, meaning that it migrated inwards close to Mars's current orbit and then back away again. This is thought to have prevented the inner planets growing as large as they typically do in other, so-far-discovered, planetary systems, and also diverted water-rich asteroid belt material inwards to bombard the inner planets. Without this process Earth would have much less water.

2. The moon is huge compared to the earth - no other satellite comes near. The best existing theory of its origin is an early collision between two planet-sized objects that knocked enough material into orbit that then coalesced into the moon. When random planetary collisions are modelled, such a collision that doesn't either shatter both planets into millions of small asteroids or result in a single large body is exceedingly unlikely.

The moon exerts a great stabilizing influence (preventing the earth's axis of spin wobbling around as much as it otherwise would) and so creates more stable seasons over geological time. It also raises sizeable regular tides in the oceans, which maybe are helpful to evolution?

If a planet needs to sustain a climate where liquid water exists continuously for many hundreds of millions, or even billions of years in order for intelligent life to evolve, then current theories suggest that such planets may be vanishingly rare.
__________________
Reply With Quote
Thanks, from:
Ari (06-22-2019), chunksmediocrites (07-01-2019), Crumb (06-19-2019), JoeP (06-19-2019), Kyuss Apollo (06-19-2019), SR71 (06-21-2019), Stormlight (06-20-2019), The Lone Ranger (06-19-2019)
  #11  
Old 06-25-2019, 07:33 PM
But's Avatar
But But is offline
This is the title that appears beneath your name on your posts.
 
Join Date: Jun 2005
Gender: Male
Posts: MVDCCLXIV
Default Re: A Sample of...One

Quote:
Originally Posted by ceptimus View Post
If a planet needs to sustain a climate where liquid water exists continuously for many hundreds of millions, or even billions of years in order for intelligent life to evolve, then current theories suggest that such planets may be vanishingly rare.

And yet the preponderance of the evidence tells us that there are three such bodies in our solar system alone: Earth, Europa and Enceladus. There is some circumstantial evidence that the latter two have hydrothermal vents like our Last universal common ancestor - Wikipedia probably lived around.


That kind of environment (frozen water at the top, boiling water at the bottom) under a kilometers thick ice shell may be a lot more stable and hospitable to life than the average planet with a thin atmosphere. I wouldn't be all that surprised if we melted through the ice on Europa and something bit the camera.
Reply With Quote
Thanks, from:
ceptimus (06-25-2019), Stormlight (11-06-2019), The Lone Ranger (06-26-2019)
  #12  
Old 06-27-2019, 08:10 AM
Kyuss Apollo's Avatar
Kyuss Apollo Kyuss Apollo is offline
happy now, Mussolini?
 
Join Date: May 2006
Location: location, location
Posts: VDCCXXIII
Blog Entries: 7
Images: 17
Default Re: A Sample of...One

Quote:
Originally Posted by But View Post
Quote:
Originally Posted by ceptimus View Post
If a planet needs to sustain a climate where liquid water exists continuously for many hundreds of millions, or even billions of years in order for intelligent life to evolve, then current theories suggest that such planets may be vanishingly rare.

And yet the preponderance of the evidence tells us that there are three such bodies in our solar system alone: Earth, Europa and Enceladus. There is some circumstantial evidence that the latter two have hydrothermal vents like our Last universal common ancestor - Wikipedia probably lived around.

That kind of environment (frozen water at the top, boiling water at the bottom) under a kilometers thick ice shell may be a lot more stable and hospitable to life than the average planet with a thin atmosphere. I wouldn't be all that surprised if we melted through the ice on Europa and something bit the camera.
That would be awesome if something did swim by the camera, even if it were a microscopic something. But note the key conditional words in your second paragraph -- an "ice shell may be" more hospitable to life and "if" after we melted through the ice on Europa "something bit the camera." All circumstantial evidence and maybes aside, until we have that second data point for abiogenesis it is all speculation.

I am not denying the possibility of such life forms, but at the moment there is no actual evidence for them. So then, what is this? Wishful thinking? I am arguing that yes, it is. There is certainly no evidence of a second abiogenesis in the fossil record, in nature, in the lab, or in any of our observations and explorations of space.

If life really were easy peasy, this place would be swarming with Klingons, and its not. If SETI has proven anything, it is that we are definitely not sitting in the middle of an intergalactic empire. Not even the crickets are chirping.

What is backed by science is that an extraordinary set of circumstances, piled up over the course of billions(!) of years, preceded our appearance -- intelligent beings with a capacity for abstract reasoning, for self-awareness, and more recently a realization of just how fortuitous we are to be sitting here wondering about all this in the first place. These are the factors that the Drake Equation attempts to quantify. The constituent parts of the Drake Equation, like the "fraction of stars with planets," the "fraction of planets that are habitable" and the "fraction of existing life forms that develop intelligence" all make sense as part of a thought experiment. But with a data point of exactly one, we really have no idea what numbers to plug into the Drake Equation:

Quote:
N = R * fp * ne * fl * fi * fc * L

That's the entire Drake Equation. As far as formulae go, it's very simple. We want know N, the number of civilizations we might hope to detect by telescope. The problem is in the parameters all multiplied together -- all those f's and n's and so forth. Out of those seven variables, we know the exact value of none of them.

We have a very rough estimate of the first variable and a foothold on the second; the remaining five are posed in such a way that they are essentially impossible to measure...


The worst thing about the Drake equation is that it gives us a false idea of grasping the problem we are trying to solve. A mathematical equation connotes some scientific study or understanding of a subject. But this is misleading: SETI is simply NOT a scientific endeavor. It's entirely a leap of faith, albeit a leap that uses tools devised by science. It's like searching for paranormal activity with an electronic sound recorder. [all emphasis mine]
It is easy to point out the fallacies in other beliefs, like belief in an afterlife or in the miracles of Jesus or in the existence of Allah, or Zeus, or the Flying Spaghetti Monster. I have a very healthy skepticism for pretty much everything that involves any "magical thinking" and "leaps of faith" with no scientific evidence to support the given conclusion, as I suspect does pretty much everyone that has commented in the thread. But until we have hard scientific evidence, isn't this argument that there just has to be life out there in the solar system, galaxy, or universe just that, a belief? A hope? A leap of faith?

Albeit the existence of life beyond the Earth has a much greater probability to be true than, let's say, the idea that Moses parted the Red Sea, it's a conclusion based on a belief nonetheless. And while the "absence of evidence is not evidence of absence," that truism only points out there is a possibility of life out there; it does not provide proof of it.
__________________
This week's track: Earthlesss - Godspeed




Reply With Quote
Thanks, from:
But (06-27-2019), ceptimus (06-27-2019), Stormlight (11-06-2019)
  #13  
Old 06-27-2019, 03:03 PM
The Lone Ranger's Avatar
The Lone Ranger The Lone Ranger is offline
Jin, Gi, Rei, Ko, Chi, Shin, Tei
 
Join Date: Jul 2004
Posts: MXDX
Images: 523
Default Re: A Sample of...One

Quote:
Originally Posted by Kyuss Apollo View Post
If life really were easy peasy, this place would be swarming with Klingons, and its not. If SETI has proven anything, it is that we are definitely not sitting in the middle of an intergalactic empire. Not even the crickets are chirping.
This does not follow. Life might be very common, for all we know (I'm not saying it is, by the way), but even if life is relatively common, it does not then follow that intelligent life is common at all. The best evidence we have suggests that abiogenesis probably isn't difficult on a planet similar to Earth, and there are certainly a lot of those in the Universe. But intelligent life has evolved only once in Earth's history -- suggesting that even if the Universe is teeming with life, the evolution of intelligent life is anything but inevitable.


Quote:
And while the "absence of evidence is not evidence of absence," that truism only points out there is a possibility of life out there; it does not provide proof of it.
Exactly no one here has suggested that we have proof of extraterrestrial life. What pretty-much everyone has gone out of their way to point out is that we simply don't have enough data to truly judge how common (or rare) extraterrestrial life might be -- and that even if life is relatively common, "intelligent" life probably isn't.

And more to the point, given the vast distances and the immense time scales involved, the probability that two or more civilizations could coexist and somehow encounter each other are exceedingly remote. So, for practical purposes, we almost-certainly are alone in the Universe.

In the sense that even if extraterrestrial civilizations do exist (or have existed in the past, or will exist in the future), we'll almost-certainly never know about it.



I would certainly agree that if anyone thinks there's anything other than the remotest of chances that S.E.T.I. will ever pick up an extraterrestrial transmission, they're dreaming. As such, it's probably a great big waste of time and money. On the other hand, I can certainly think of worse ways to spend time and money.
__________________
“The greatest way to live with honor in this world is to be what we pretend to be.”
-- Socrates
Reply With Quote
Thanks, from:
But (06-27-2019), ceptimus (06-27-2019), ChuckF (06-27-2019), JoeP (06-27-2019), Kyuss Apollo (06-28-2019), slimshady2357 (06-27-2019), Stormlight (11-06-2019)
  #14  
Old 06-27-2019, 07:03 PM
But's Avatar
But But is offline
This is the title that appears beneath your name on your posts.
 
Join Date: Jun 2005
Gender: Male
Posts: MVDCCLXIV
Default Re: A Sample of...One

Quote:
Originally Posted by The Lone Ranger View Post
I would certainly agree that if anyone thinks there's anything other than the remotest of chances that S.E.T.I. will ever pick up an extraterrestrial transmission, they're dreaming. As such, it's probably a great big waste of time and money. On the other hand, I can certainly think of worse ways to spend time and money.

That. I just read a bit through one of the latest SETI papers and the numbers given in there. They looked at 1700 of the nearest stars I think, which is a microscopic fraction of the stars in our galaxy, and what they really learned was that near those stars, no one was either (for whatever reason) operating a transmitter with way more power than all electricity on Earth or blasting right at us with a smaller one. Well, one in the range between 1.1 and 3.45 GHz, to be more precise. With those methods, you couldn't detect our civilization even now.
Reply With Quote
Thanks, from:
ChuckF (06-27-2019), Crumb (06-27-2019), Kyuss Apollo (06-28-2019), Stormlight (11-06-2019), The Lone Ranger (06-27-2019)
  #15  
Old 06-27-2019, 10:03 PM
JoeP's Avatar
JoeP JoeP is offline
YELLOW HAIR FAKE ANIMAL
 
Join Date: Jul 2004
Location: England/Miisaland
Gender: Male
Posts: XXVMCMLXXXVII
Images: 18
Default Re: A Sample of...One

Quote:
Originally Posted by The Lone Ranger View Post
This does not follow. Life might be very common, for all we know (I'm not saying it is, by the way), but even if life is relatively common, it does not then follow that intelligent life is common at all. The best evidence we have suggests that abiogenesis probably isn't difficult on a planet similar to Earth, and there are certainly a lot of those in the Universe. But intelligent life has evolved only once in Earth's history -- suggesting that even if the Universe is teeming with life, the evolution of intelligent life is anything but inevitable.
It's certainly not common on earth. I'm not sure that there is any intelligent life on earth.

I mean, srsly, on a (very short) millennial scale, it's not looking all that likely that human 'intelligence' is all that adaptive. We're really bad at understanding long-term consequences and adapting our behaviour to long-term risks. All our intelligence might achieve is taking a lot of other species down with us.
__________________

:roadrun:
Free thought! Please take one!

:unitedkingdom:   :southafrica:   :unitedkingdom::finland:       :eur:       :m&ms::m&ms::twix::twix: (rotated 180°):m&ms::m&ms:
Reply With Quote
Thanks, from:
Kamilah Hauptmann (06-28-2019), Kyuss Apollo (06-28-2019), Stormlight (11-06-2019), The Lone Ranger (06-27-2019)
  #16  
Old 06-19-2019, 12:13 PM
JoeP's Avatar
JoeP JoeP is offline
YELLOW HAIR FAKE ANIMAL
 
Join Date: Jul 2004
Location: England/Miisaland
Gender: Male
Posts: XXVMCMLXXXVII
Images: 18
Default Re: A Sample of...One

But what's your vote? The outcome hinges on that conditional - if sustained liquid water is needed for intelligence to evolve.

It seems suspiciously easy to find reasons why the conditions that led to the one* observable instance of intelligent life that we recognise may be vanishingly rare. We don't have any real evidence that "intelligence" needs to resemble us.

* There might be others we've already observed, but we're not doing very well learning to communicate with octopuses or crows or chimpanzees (problem solving, tool using, complex communications).
__________________

:roadrun:
Free thought! Please take one!

:unitedkingdom:   :southafrica:   :unitedkingdom::finland:       :eur:       :m&ms::m&ms::twix::twix: (rotated 180°):m&ms::m&ms:
Reply With Quote
Thanks, from:
chunksmediocrites (07-01-2019), Crumb (06-19-2019), Kyuss Apollo (06-22-2019), SR71 (06-21-2019), Stormlight (06-20-2019), The Lone Ranger (06-19-2019)
  #17  
Old 06-19-2019, 12:20 PM
JoeP's Avatar
JoeP JoeP is offline
YELLOW HAIR FAKE ANIMAL
 
Join Date: Jul 2004
Location: England/Miisaland
Gender: Male
Posts: XXVMCMLXXXVII
Images: 18
Default Re: A Sample of...One

Something that occurred to me yesterday ... maybe in the near future (years/decades) we'll have enough simulation power to create virtual universes and get "experimental" values for the variables in the Drake equation. And if (a big if) we manage not to embed our prejudices about what life and intelligence are, we might be able to assess the probability of self-protecting, self-reproducing, communicating things arising. (We haven't been very good at keeping prejudices out of AI systems so far.)

Given the vast distances and travel times to other stars compared to the human scale, maybe we'll create simulated intelligence before we discover it elsewhere...
__________________

:roadrun:
Free thought! Please take one!

:unitedkingdom:   :southafrica:   :unitedkingdom::finland:       :eur:       :m&ms::m&ms::twix::twix: (rotated 180°):m&ms::m&ms:
Reply With Quote
Thanks, from:
chunksmediocrites (07-01-2019), Kyuss Apollo (06-22-2019), Stormlight (06-20-2019)
  #18  
Old 06-19-2019, 01:44 PM
ceptimus's Avatar
ceptimus ceptimus is offline
puzzler
 
Join Date: Aug 2004
Location: UK
Posts: XVDCCCLXXVI
Images: 28
Default Re: A Sample of...One

I'm of the opinion that species capable of space travel that are only a few hundred years more advanced than ourselves are vanishingly rare - otherwise we would have seen the evidence by now. I think if we are still around in a few hundred years, we'll then have the capability to send out self-replicating probes which will then spread out and multiply exponentially to explore the galaxy over the next few tens/hundreds of millions of years.

A few hundred million years is nothing when compared to the age of the universe, so you'd expect that if other space-travelling species have existed, at least one of them would have evolved early enough that we should see their probes here by now.
__________________
Reply With Quote
Thanks, from:
Crumb (06-19-2019), JoeP (06-19-2019), Kyuss Apollo (06-22-2019), Stormlight (06-20-2019), The Lone Ranger (06-19-2019)
  #19  
Old 06-20-2019, 02:20 AM
ChuckF's Avatar
ChuckF ChuckF is offline
liar in wolf's clothing
 
Join Date: Feb 2005
Location: Frequently about
Posts: XVMMMCMXXXII
Images: 2
Default Re: A Sample of...One

I agree with JoeP and Sack and TLR

I think it is very likely that there is (some kind) of other life form out there somewhere, just based on the vast scale of the universe. And maybe there is even some form of microbial life in the solar system, which would be neat.

But I think it is unlikely to matter outside of thought experiments, for the simple reason that it is very unlikely we will ever encounter it. In part because of the vastness and the possibly insurmountable challenges of interstellar travel, in part because of the nebulous and anthropocentric thinking about the term "life," but mostly because we are not likely to survive long enough to encounter it. In terms of awareness of space and spacefaring, we are infants. We have only been dimly aware of our immediate cosmic surroundings for a few decades. Orbital travel is still an expensive and dangerous proposition.

Thus far, we have had only a very, very narrow window for comprehensible contact with intelligence, or a search for non-intelligent life. At the moment, we seem much more likely to destroy ourselves as a species in the near term than continue looking long enough to find some other life form, intelligent or not. So whatever the odds that we are objectively alone or not, I think the last humans will die without ever having found extraterrestrial life, which is pretty much the same as being alone.
Reply With Quote
Thanks, from:
ceptimus (06-20-2019), chunksmediocrites (07-01-2019), Crumb (06-20-2019), JoeP (06-20-2019), Kyuss Apollo (06-20-2019), slimshady2357 (06-20-2019), Sock Puppet (06-20-2019), Stormlight (06-20-2019), The Lone Ranger (06-20-2019)
  #20  
Old 06-20-2019, 08:36 AM
erimir's Avatar
erimir erimir is offline
Projecting my phallogos with long, hard diction
 
Join Date: Sep 2005
Location: Dee Cee
Gender: Male
Posts: XMMMCCXXVI
Images: 11
Default Re: A Sample of...One

And even if we suppose that there is intelligent life out there and humans may eventually contact it, we will probably all be long dead before it happens.

Unless we're in a Star Trek or Star Wars-like universe that is teeming with hundreds or thousands of interstellar spacefaring sentient species in our galaxy, but in that case, they're taking their damn time. Surely some empire should've come and colonized us by now.
Reply With Quote
Thanks, from:
Stormlight (11-06-2019)
  #21  
Old 06-20-2019, 11:42 AM
JoeP's Avatar
JoeP JoeP is offline
YELLOW HAIR FAKE ANIMAL
 
Join Date: Jul 2004
Location: England/Miisaland
Gender: Male
Posts: XXVMCMLXXXVII
Images: 18
Default Re: A Sample of...One

Quote:
Originally Posted by ceptimus View Post
A few hundred million years is nothing when compared to the age of the universe, so you'd expect that if other space-travelling species have existed, at least one of them would have evolved early enough that we should see their probes here by now.
Quote:
Originally Posted by erimir View Post
Surely some empire should've come and colonized us by now.
Yes but.

Speed of light; number of star systems in the galaxy (say 1 billion of the say 100 billion stars).

The galaxy could be riddled with intelligent space-faring civilisations right now, and even some which have 'survived' for the necessary millions of years (survived but changed by the experience, possibly evolved, they may not even all speak English any more).

But if you've colonised millions of planets across the galaxy, that's still about 0.1% of the available planets. How frequently are you going to check each candidate planet? Once your automated probes detect something, how long is it going to take the alert to get back to the nearest research facility / the Contact division? And how long will it take for the ambassadors / merchants / spies / warships to reach the candidate planet? Hundreds of years at least. Which is no time at all compared to the millions of years you've been managed your galactic empire, but a pretty long time for puny humans.

If there are enough planets giving rise to intelligent and communicating species, then we can expect a vastly greater number to sustain non-intelligent and non-communicating life forms or systems. Why would you bother to check every single one more often than every million years? I don't think the above kinds of arguments give proper considerations to the timescales involved.

In other words ... there might be a lot of civilisations out there of the kind we would try to contact ... but we are not remotely special or unique.
__________________

:roadrun:
Free thought! Please take one!

:unitedkingdom:   :southafrica:   :unitedkingdom::finland:       :eur:       :m&ms::m&ms::twix::twix: (rotated 180°):m&ms::m&ms:
Reply With Quote
Thanks, from:
But (06-25-2019), Stormlight (06-25-2019)
  #22  
Old 06-20-2019, 01:28 PM
ChuckF's Avatar
ChuckF ChuckF is offline
liar in wolf's clothing
 
Join Date: Feb 2005
Location: Frequently about
Posts: XVMMMCMXXXII
Images: 2
Default Re: A Sample of...One

Quote:
Originally Posted by JoeP View Post
The galaxy could be riddled with intelligent space-faring civilisations right now, and even some which have 'survived' for the necessary millions of years (survived but changed by the experience, possibly evolved, they may not even all speak English any more).
buh how they gonna read their bible then huh?
Reply With Quote
Thanks, from:
Stormlight (06-25-2019)
  #23  
Old 06-20-2019, 04:55 PM
JoeP's Avatar
JoeP JoeP is offline
YELLOW HAIR FAKE ANIMAL
 
Join Date: Jul 2004
Location: England/Miisaland
Gender: Male
Posts: XXVMCMLXXXVII
Images: 18
Default Re: A Sample of...One

Quote:
Originally Posted by ChuckF View Post
Quote:
Originally Posted by JoeP View Post
The galaxy could be riddled with intelligent space-faring civilisations right now, and even some which have 'survived' for the necessary millions of years (survived but changed by the experience, possibly evolved, they may not even all speak English any more).
buh how they gonna read their bible then huh?
we goan hafta translate it! Missionaries! in! space!
__________________

:roadrun:
Free thought! Please take one!

:unitedkingdom:   :southafrica:   :unitedkingdom::finland:       :eur:       :m&ms::m&ms::twix::twix: (rotated 180°):m&ms::m&ms:
Reply With Quote
Thanks, from:
Stormlight (06-25-2019)
  #24  
Old 06-21-2019, 01:37 AM
erimir's Avatar
erimir erimir is offline
Projecting my phallogos with long, hard diction
 
Join Date: Sep 2005
Location: Dee Cee
Gender: Male
Posts: XMMMCCXXVI
Images: 11
Default Re: A Sample of...One


:cylon:
Reply With Quote
Thanks, from:
ChuckF (06-21-2019), Stormlight (06-25-2019)
  #25  
Old 06-21-2019, 12:20 PM
MonCapitan2002's Avatar
MonCapitan2002 MonCapitan2002 is offline
Servant of the Dark Lord
 
Join Date: Jan 2005
Gender: Bender
Posts: VMMMCLXXXI
Blog Entries: 12
Images: 1
Default Re: A Sample of...One

I am of the opinion that it's entirely possible that life could be rare, but the fact of the matter is that we simply don't have enough data to make any determination on how common intelligent (defined here as tool using and capable of developing advanced technology) life is. After all, we only have the sample size of one biosphere to evaluate the odds with.

It is very likely that the answer may never be discovered. It almost certainly won't be discovered in our lifetimes absent a ground breaking discovery of some nature. Personally, I hope that the universe is filled with countless interstellar civilizations and will be among them, but realistically calling that exceedingly unlikely is a monumental understatement.
__________________

Allan Glenn. 1984-2005 RIP
:countsheep::countsheep::countsheep::countsheep::countsheep::countsheep::countsheep::countsheep::countsheep::countsheep::countsheep:
Under no circumstances should Quentin Tarantino be allowed to befoul Star Trek.
Reply With Quote
Thanks, from:
Ari (06-21-2019), ceptimus (06-21-2019), JoeP (06-21-2019), Kyuss Apollo (06-21-2019), Stormlight (06-25-2019)
Reply

  Freethought Forum > The Marketplace > The Sciences


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

 

All times are GMT +1. The time now is 05:33 PM.


Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Page generated in 1.92903 seconds with 15 queries