113 réponses à ce sujet

[caradoc2000]

What's more amazing that we aren't alone, or that we are?

We aren't sure whether we know if we are alone - or not.

[metatheurgist]

What's more amazing? That we aren't alone, or that we are?

As someone much smarter and more famous than me said: "Both are equally terrifying."

[Allan Schumacher]

On a more serious note, this may be an indictment of FTL travel more than anything else. Or, perhaps, that if it is possible, the difficulty in either discovering it or, perhaps more likely, the massive amount of resources it may take.


Either way, we won't know until we travel to the closest star. That's when the fun starts.

 

 

The Fermi Paradox is pretty much exactly the indictment of interstellar travel.  Either that, or Earth is more of a special snowflake than we realize, and sentient life throughout the galaxy isn't that common.

 

Or we're first, but that's not the betting man's choice.

[Fast Jimmy]

The Fermi Paradox is pretty much exactly the indictment of interstellar travel.  Either that, or Earth is more of a special snowflake than we realize, and sentient life throughout the galaxy isn't that common.
 

Or we're first, but that's not the betting man's choice.

It does make one question the concept that sentient life is the "end goal" of evolutionary forms of life. It has let humanity expand and become masters of our planet and now are even looking out beyond the stars. But really, that's not what evolution does - it isn't designed to make any species the apex of not only their entire ecosystem, but of all possible ecosystems. Evolution is all about being the most adapted to survive in an environment with consuming the least amount of resources.

The circumstances believed to have occuree to allow sentient life for humans - a community type species, the presence of a variety of foods (and sources of nutrition) and no natural predators... these are rare circumstances in our native world ecology. Maybe our belief that "a planet with life will naturally produce sentient life" may be the result of a huge confirmation bias. There could be thousands upon thousands of planets that support life in the galaxy, but none that have had the biological fluke of having a species develop a biological cognitive system that would less to societal advances.

[Kaiser Arian XVII]

It does make one question the concept that sentient life is the "end goal" of evolutionary forms of life. It has let humanity expand and become masters of our planet and now are even looking out beyond the stars. But really, that's not what evolution does - it isn't designed to make any species the apex of not only their entire ecosystem, but of all possible ecosystems. Evolution is all about being the most adapted to survive in an environment with consuming the least amount of resources.
 

 

Let's see. 99% of animals failed miserably after a climate change or confronting a kind of new hunter. Humankind is the only species who can actually "adapt" by using the mind and making instruments.

 

Creatures like cockroaches and rats are very adaptable too, but by using evolutionary adaption and strong physical features.

So...

 

 

lol

[Fast Jimmy]

Let's see. 99% of animals failed miserably after a climate change or confronting a kind of new hunter. Humankind is the only species who can actually "adapt" by using the mind and making instruments.

Creatures like cockroaches and rats are very adaptable too, but by using evolutionary adaption and strong physical features.
So...



lol

One cannot contest the value of intelligence to survivability and being the fittest animal in any environment.

However, being an intelligent Tyranssuarus Rex that can see in the dark and fly would be even better. Yet that didn't happen - genes can't do everything. Nutrition is equally important. One has to be able to eat or otherwise obtain all the nutrients, minerals, amino acids, etc. to support the mechanisms. And not just support it during the best times, but in the leanest and hardest of times.

The amount of vitamins, minerals and amino acids humans use to support our brains require one of the most varied diets of any species on the planet. Fruits, vegetables, grains, proteins... it requires not just a wide diet but a number of different means to getting food. And it would have required all of these nutrients in order for the brain to evolve, so humans (or, more accurately, our ancestors) would had to have been doing all the work for millions of years before the brains would have developed enough to begin developing tools and other forms of advanced cognitive thought.

So, in that light, it seems a little unlikely that evolution would pop that result out in every instance of life, as it presupposes millions of years of evolutionary success to even get to the stage of sentience. Which, at that point... why need sentience?

[bEVEsthda]

I don't believe in the Fermi Paradox. It's simply wrong.

The Galaxy is vast. I also think it might be quite young in terms of technological civilizations. Also, planets with the right kind of conditions are rare. I believe there are enough planets in the galaxy to make the total number of suitable planets quite significant, but they don't exactly rub themselves against each other. Sure, some kind of "life" can probably originate in many kinds of environments, but to embark on the path of greatly increased complexity and survive environmental changes takes a deal. The planet needs to have a magnetic field to divert the radiation and solar wind from the sun. Else the atmosphere will dissappiate away into space, as well as making life as we know it impossible on the surface. And life has to evolve on land, otherwise there will never be a technological species. The planet needs to have a large moon to stabilize it's rotation axis, or vastly fluctuating conditions would periodically exterminate all life. And there should have been a large collision to bring up mineral resources to the surface crust.

 

If a civilization survives, and continues to evolve in a manner that results in increasing technical engineering capacity, - instead of focusing on packing the highest number of individuals into an overpopulated planet, and living virtual lives in electronic devices, - then I think it's inevitable that attempts are eventually made to colonize other solar systems.

But that is not a simple undertaking, not even for an advanced civilization. Because I do not think "advanced" means that more and bigger becomes easier or cheaper. In Fermi's days that might have seemed to be the case, but we know better today. And more and bigger is what it takes. To get people there and prepare things so they can survive. There's always also the question "why", which will be asked in any such civilization. The answer to that is selvevident: Because life want to migrate and spread. Because you don't put all your eggs in one basket. Because a number of global extinction events will happen, with 100% certainty. Because the Sun will die. But those answers mean nothing to the 'here and now' for the people of any technical civilization, at any time. They will demand other things from their politicians.

 

So no, I don't think the Galaxy would have been colonized in a jiffy. It will happen, but the hour is probably still young. Since it's probably quicker and easier to build artificial worlds, in space, to populate, than remake and re-arraign entire planets to support life, an advanced civilization will probably be content with doing that, for a long time, in its own solar system, before stretching out to another sun. There has to be something driving that. Demand for more resources, A dying sun, or maybe simply the demand for the luxury of planetside living?

[Shermos]

I personally lean towards the hyper advanced aliens hypothesis. The climate change hypothesis is just interesting, and quite possibly at least partially correct.

 

We have to consider that the universe is 13.7 billion years old, and stars capable of supporting planets like ours have been around for somewhere close to 10 billion years according to currently accepted theories. That means there could be civilisations - even ones which originated in our galaxy - which are billions of years ahead of us. A greater number still could be millions of years ahead of us. Such civilisations are beyond our ability to imagine and it's the height of arrogance to assume we could detect their presence with our current abilities.

 

This hypothesis still leaves us open to detecting civilisations near to our level, but the nearest to us could be on the other side of the galaxy, or has not built any structures we can detect as yet.  

[Dovahzeymahlkey]

I think the more long-lived a civilization is, the more likely it is to destroy itself or be destroyed until it reaches a point where its absolutely going to be destroyed. Maybe thats why we dont see spaceships whizzing about.

[Lotion Soronarr]

 Such civilisations are beyond our ability to imagine and it's the height of arrogance to assume we could detect their presence with our current abilities.

 

I don't see why not.

Aliens are material beings living in a material universe, leaving material evidence behind. They aren't ghosts.
 

Unless you believe in that "ascending to a higher plane of existence" crap.

[Obadiah]

Does the Fermi paradox take into account the possibility that, while theoretically possible, most alien civilizations ultimately decide that interstellar travel is not worth the cost in lives and resources?
 
I say "cost in lives" because, unless you're able to travel at a significant fraction of the speed of light, you probably can't go very far without "generational ships" and distant colonies that would have little or no meaningful contact with the presumably more developed homeworld. As intrigued as I am by space travel and the possibility of alien life, I don't think I would willingly sign up for such a mission when, in all likelihood, I wouldn't even live long enough to be there when we actually reach other solar systems. I suppose some sort of cryostasis is another theoretical possibility, but again, that means saying goodbye for good to anyone left behind, even if we're talking about species with longer life spans.
 
Or does the Fermi paradox posit that, whatever the obstacles, *somebody* would eventually take the leap if it's possible to do so?

The early colonists to different parts of the Earth did say goodbye to everyone they knew (easier because sometimes they just hated them), to start colonies on some different continent.

Generation ships with no hope of ever seeing their loved ones again are an easier thing to understand for societies that see themselves less as individuals and more as a species. Or, the more dire option, societies that simply have no choice because their own planet is dying out. Either of those could happen here on Earth eventually. (Hmm, I think I actually got those motivations from the protagonists in the trailer of that new Chris Nolan movie Interstellar).

[Fast Jimmy]

God creates dinosaurs.
God kills dinosaurs.
God creates Man.
Man kills God.
Man creates dinosaurs.



Dinosaurs eats Man... Woman inherits the Earth.


Not that relevant, but still, it always makes me giggle.

[FlyingSquirrel]

What's more amazing? That we aren't alone, or that we are?

 

If it turns out that the conditions for sentient life, and in turn for intelligent, self-improving sentient life, are actually very rare, then I could swallow us being alone in the galaxy. If it turned out we were alone in the entire *universe*, I'd be very surprised.

[FlyingSquirrel]

One other thing to consider, I suppose, is that a civilization could reach fairly high levels of development in terms of overcoming material scarcities and achieving a high quality of life but still be very different from humans psychologically. Part of the reason we're drawn to space exploration is that we have a fascination with the idea of other worlds and other life forms, but what if there were an alien race that simply didn't care about such issues? Or say the balance between curiosity and fear of the unknown is more heavily tilted towards the latter for them, and they're scared that they might be asking for trouble if they contacted other advanced species.

[CavalierToast]

As someone much smarter and more famous than me said: "Both are equally terrifying."

Nonsense, if we are alone, we I can rule the universe.

If we are not alone, I we can murder knife the aliens, and then we I can rule the universe.

 

And should you disagree, we I can ...

[RainyDayLover]

We human beings are very near-sighted and have such a myopic view of the world around us. Ya'll need to "zoom out" a level or two: https://www.youtube....h?v=ppyF1iQ0-dM

[Lotion Soronarr]

I don't see a sentient race colonizing the galaxy in a heartbeat.

 

The Galaxy is huge. The distances are HUGE. And it's not like you'll be constantly expanding.

That colony ship will be immensely expensive and will be travelling for thousands of years.

Then, when it arrives, the colonists will have the entire planet to themsleves. They won't be immediately start building another colony ship and colonizing further. No, they will spend the next 10.000 years or so developing the planet they're on.

So the rate of expansion will be slow. Very slow.

Not to mention technical failures and disasters which will certainly see many colony ships fail.

 

If all of humanity would focus on colonizing the start and starts right now, I don't see us having more than 100 colonies in the next million years.

[Fast Jimmy]

I don't see a sentient race colonizing the galaxy in a heartbeat.

The Galaxy is huge. The distances are HUGE. And it's not like you'll be constantly expanding.
That colony ship will be immensely expensive and will be travelling for thousands of years.
Then, when it arrives, the colonists will have the entire planet to themsleves. They won't be immediately start building another colony ship and colonizing further. No, they will spend the next 10.000 years or so developing the planet they're on.
So the rate of expansion will be slow. Very slow.
Not to mention technical failures and disasters which will certainly see many colony ships fail.

If all of humanity would focus on colonizing the start and starts right now, I don't see us having more than 100 colonies in the next million years.

I think the point is that even millions of years, in a galactic timeline, is very quick. When you consider entire star systems have loved and died in our galaxy (not to mention our universe) that could have possibly supported life and a sentient race before our sun even came into existence, it seems statistically improbably (through one lense) that none of them created a space daring species that was able to colonize the galaxy over thousands or even millions of years without leaving any traces, such as radio wave communications or other energy signatures. We can detect remnants of the Big Bang floating around the universe, but haven't found a single alien version of Baywatch. That could be pretty telling that there never is nor was any other space faring races.

[Lotion Soronarr]

1 radio waves aren't eternally detecable.

Like ripples in the water, even if some alien race did watch TV and emitted radio signalns, It could very well be those signals passed over us without us detecting them (because we either couldn't or were looking in a different direction).

 

In other words, detection has a time window. If you miss it, you missed it.

 

And yes, I know millions of years is not mach on a galactic scale, but still.

If humanity is any indication, I don't see any race populating the entire galaxy, as there simply is no need. Population expansion seems to be slowing down.

[Kaiser Arian XVII]

Humankind has advanced greatly in the last 6000 years. From the simplest villagers with simplest instruments to computer programs, nanotechnology, atomic power, solar system survey and etc.

It has been really fast... but we might confront some kind of mental or resource obstruction that may lower our innovation rate severely. Optimistically in the next 3000 years we can create dozens of colonies across the galaxy. With considering both positive and negative elements we can create a few colonies outside of solar system in the next 6000 years (those colonies are far and rare).

The worst scenario is that we can't even go outside of solar system and all our efforts will fail!

[FlyingSquirrel]

Humankind has advanced greatly in the last 6000 years. From the simplest villagers with simplest instruments to computer programs, nanotechnology, atomic power, solar system survey and etc.

It has been really fast... but we might confront some kind of mental or resource obstruction that may lower our innovation rate severely. Optimistically in the next 3000 years we can create dozens of colonies across the galaxy. With considering both positive and negative elements we can create a few colonies outside of solar system in the next 6000 years (those colonies are far and rare).

The worst scenario is that we can't even go outside of solar system and all our efforts will fail!

 

For me, it comes back to the question of whether the fact that we could necessarily means that we would. I mean, we already have the technology to go to the Moon, and could probably stretch it for a manned mission to Mars if some astronauts didn't mind the risks and the long trip, but it costs too much to do that when we're pressed to pay for other priorities and we can still do some exploration with remote probes.

 

Space exploration is interesting, sure, but it doesn't have that many immediate practical applications at the moment. It might theoretically solve some of our sustainability problems if we knew of another inhabitable planet that we could reach quickly, but right now we don't, and I doubt that terraforming the Moon or Mars would have a higher cost/benefit ratio than strictly Earth-based solutions with the current available technology. And, I suppose, it's a potential escape hatch if an existential threat manifests itself. Contacting aliens, if they're out there, would be a major revelation but it could also pose a risk if the aliens were to decide to raid Earth for resources or otherwise turned hostile.

[Gravisanimi]

Why find planets to colonize when they are so far away when you can make a solar system of viable planets?

 

I don't think humans are going to get to the level where they will be able to make such super-structures, but if it happens before a FTL form of transportation, I would put my lot in that hat.

[Fast Jimmy]

Why find planets to colonize when they are so far away when you can make a solar system of viable planets?

I don't think humans are going to get to the level where they will be able to make such super-structures, but if it happens before a FTL form of transportation, I would put my lot in that hat.

Eh. Solar system creation takes a LONG LONG LONG time. You have to create a singularity, have it collect mass, reach critical values, go into a state where is begins flinging out planets, have them settle into stable orbits, have their surfaces cool and atmospheres developed, seed it with life and hope for the best.

At that level of time, resource and necessary scientific advancement, it would be easier to terraform more planets in our solar system or nearby solar systems. Nearby systems can be terraformed within >1,000 years with travel from more conventional thrusters, which is a heck of a lot faster than we could make a habitable solar system.

[Fast Jimmy]

For me, it comes back to the question of whether the fact that we could necessarily means that we would. I mean, we already have the technology to go to the Moon, and could probably stretch it for a manned mission to Mars if some astronauts didn't mind the risks and the long trip, but it costs too much to do that when we're pressed to pay for other priorities and we can still do some exploration with remote probes.
 
Space exploration is interesting, sure, but it doesn't have that many immediate practical applications at the moment. It might theoretically solve some of our sustainability problems if we knew of another inhabitable planet that we could reach quickly, but right now we don't, and I doubt that terraforming the Moon or Mars would have a higher cost/benefit ratio than strictly Earth-based solutions with the current available technology. And, I suppose, it's a potential escape hatch if an existential threat manifests itself. Contacting aliens, if they're out there, would be a major revelation but it could also pose a risk if the aliens were to decide to raid Earth for resources or otherwise turned hostile.

Any form of colonization is a huge upfront investment and gamble. For Columbus to "discover" America, it required huge government backing, just like space travel does today. Colonization of the Americas required insane investments of resources, ships and money. Yet now, the world is dependent on the economy and resources of the Western Hemisphere.

Space is a gateway into unlimited resources, space and energy. There are storms on planets in our solar system that are larger than Earth itself - what if we could tap into that as an energy source that would dwarf what petroleum gives us? The asteroid belt has more minerals and natural resources than can be found on entire continents - what if we could sustain our current quality of life through mining operations that won't run "dry" for millenia? There are moons nearby which may have enough water to not only sustain life, but offer the chance at long-term sustainability - what if we could resolve world overpopulation and hunger with a whole second, third or fourth homeworld to sustain life and crops?

Yes, there are lots of huge hurdles to overcome. But just like Europe didn't wait until it had completely mastered nautical navigation and feeding all of its citizens before it could invest huge amounts of capital into settling another continent, the same could be said of humanity and space. We must explore the boundaries of our existence and technology in ways that seem impossible today for us to keep moving towards greater events in the future. Because only by chasing the impossible do we make our reality immeasurably better.

[Gravisanimi]

I meant that as well, but certainly more viable to terraform a nearby or our own solar system.

 

Creating Dyson Spheres and Shells would be just as impressive, but not cost as much resources if we use drones to collect materials and build it, because they can go faster in space.