Solutions to the Fermi Paradox

[ChristineM]

It seems saying "if there is no life out there except our own the the universe is a gigantic waste of space" implies that there is an intelligence that has the choice of using or wasting the space.

No it doesn't, it is actually a joke that implies that man is egotistical

I think future beings could be around at least a few million years. A planet about 4.25 light years away could have a lot of liquid water:

I don't, the way we are ruining our planet doesn't hold much hope for long term survival. Although it's possible.

Well apparently homo sapiens have been around about 200,000 years. BTW apparently faster than light travel is theoretically possible:

Up to 300,000 but close enough.

Hypothetically possible, there is a difference. And all experiments to attempt to make it a theory have failed.

Of course entanglement seems to say faster than light information is possible. But humans are a little bit to big for such a mode of transport

The point is that there are a lot of them. 300 million is still a lot.

Yes,

 

[excreationist]

I don't, the way we are ruining our planet doesn't hold much hope for long term survival

So every single human in existence and whatever might come after that will completely die out? Also I think ruining our planet would encourage the colonization of other planets such as the one 4.25 light years away.

Hypothetically possible, there is a difference. And all experiments to attempt to make it a theory have failed

I mean faster than light travel isn't breaking the laws of physics.

 

[ChristineM]

So every single human in existence and whatever might come after that will completely die out? Also I think ruining our planet would encourage the colonization of other planets such as the one 4.25 light years away.

Did i say that? It is my view that humanity won't last to long. Other life may and probably will last longer and evolve to cope with conditions

So when warp drive is invented there is a vhance (see below)

I mean faster than light travel isn't breaking the laws of physics.

According to Einstein's general theory of relativity, it's physically impossible for anything to travel faster than the speed of light.

 

[excreationist]

Did i say that? It is my view that humanity won't last to long.

I thought that would mean that all humans would die out. Do you think there could be beings (transhumans?) that would continue to survive? I thought hard-core survivalists would have a good chance of surviving.

Other life may and probably will last longer and evolve to cope with conditions

So all the humans would die but animals would survive?

According to Einstein's general theory of relativity, it's physically impossible for anything to travel faster than the speed of light.

Alcubierre drive - Wikipedia

en.wikipedia.org

"the Alcubierre drive is based on a solution of Einstein's field equations"
Anyway leaving the solar system to travel to a planet 4.25 light years away would be quite practical for humans in the coming centuries.

 

[Heyo]

"the Alcubierre drive is based on a solution of Einstein's field equations"

... that involves hypothesized "exotic matter" for which we have not even a hint of evidence.

Anyway leaving the solar system to travel to a planet 4.25 light years away would be quite practical for humans in the coming centuries.

With a drive powered by fusion 20% c are possible without breaking any laws of physic or relying on any other technology we don't have. Space stations like the Stanford Torus are possible entirely with existing technology.
The question is if we have the motivation and the resources to leave earth. While the motivation may rise, the resources are bound to dwindle.

 

[ChristineM]

I thought that would mean that all humans would die out. Do you think there could be beings (transhumans?) that would continue to survive? I thought hard-core survivalists would have a good chance of surviving.

I personally don't hold much hope for the survival of the human race past (guess) 500,000 years. Other animals certainly, worms razor clams etc.

So all the humans would die but animals would survive?

Those animals that are not effected by human stupidity.

"the Alcubierre drive is based on a solution of Einstein's field equations"
Anyway leaving the solar system to travel to a planet 4.25 light years away would be quite practical for humans in the coming centuries.

Hypothesis based on non existent matter.

 

[Revoltingest]

... that involves hypothesized "exotic matter" for which we have not even a hint of evidence.

With a drive powered by fusion 20% c are possible without breaking any laws of physic or relying on any other technology we don't have. Space stations like the Stanford Torus are possible entirely with existing technology.
The question is if we have the motivation and the resources to leave earth. While the motivation may rise, the resources are bound to dwindle.

Of course, reaching 20%c would mean an average speed of less.
It would take some time to accelerate to max speed, & then
decelerate to the destination.

 

[Heyo]

Of course, reaching 20%c would mean an average speed of less.
It would take some time to accelerate to max speed, & then
decelerate to the destination.

Yep. But as speed rises very quickly, even with a moderate acceleration, over a travel time of more than 20 years the acceleration/deceleration is negligible.
Fun fact: the speed limit is due to friction. At 20% c the interstellar medium is dense enough to prevent further acceleration by a fusion engine that depends on collecting the interstellar hydrogen.

 

[Revoltingest]

Yep. But as speed rises very quickly, even with a moderate acceleration, over a travel time of more than 20 years the acceleration/deceleration is negligible.
Fun fact: the speed limit is due to friction. At 20% c the interstellar medium is dense enough to prevent further acceleration by a fusion engine that depends on collecting the interstellar hydrogen.

There's also the problem of increasing mass
with speed, which slows the acceleration.

 

[Heyo]

There's also the problem of increasing mass
with speed, which slows the acceleration.

Yep, At 20% c the relative mass is about 3% bigger than the rest mass.

 

[Polymath257]

Of course, reaching 20%c would mean an average speed of less.
It would take some time to accelerate to max speed, & then
decelerate to the destination.

The real problem is that the energy involved increases as the square of the velocity (actually a bit more of you consider relativistic effects). That energy has to come from somewhere. If you use fusion, you still need to carry the fuels prior to use.

 

[Polymath257]

The Fermi Paradox is the thought that there is a high likelihood of extraterrestrial existence, yet there is no evidence for any.

What are your solutions to this paradox? I have this in Science and Religion because I'm interested in religious takes as well as scientific ones.

The idea that trips me out the most is that we are perhaps the first advanced species in the universe. The first. Well, some species has to be the first. Maybe it's actually us. What a grand and most unique opportunity this offers humanity.

Another theory I heard was that advanced alien civilizations know to stay in the dark, for fear of being wiped out by other civilizations.

What do you think?

The problem is that we only have one example of a place where life exists: the Earth. So we don't fully understand what is required to get life formed and what else it takes to get to an 'advanced' species. Going along with the question, I will assume that humans qualify as an advanced species.

So, based on what we know, what can we say about the development of life? Well, for the first thing, the basic elements (carbon, oxygen, nitrogen, sulfur, phosphorus, etc) are formed in stars at the end of their lives or in supernovae. This means that an entire stellar cycle has to have happened before life has any chance of arising. The universe is about 13.7 billion years old, and stellar cycles of the required sort can happen 'relatively fast' because the stars involved are large and go through their cycles quickly. So, we need a few billion years there.

The sun and Earth are about 4.5 billion years old, so they were formed about 9 billion years after the current expansion phase began. That is plenty of time to form the heavier elements required for life and, perhaps, there could have been life forming a few billion years before the Earth formed.

From evidence on the Earth (again, caution because of only one example), life got started easily (by about 3.8 billion years ago) and so we might expect anaerobic bacterial life to be common in the universe. ALL life on Earth was of this form until about 2 billion years ago, during the great oxygenation event. In other words, for 1.8 billion years only anaerobic bacteria lived on Earth.

During the oxygenation event, the *poisonous* oxygen was released into the atmosphere, leading to many species going extinct. This was the first major catastrophe for life on Earth (that we know about---maybe the transition from RNA to DNA was equally catastrophic). Those species that survived were able to use oxygen in their metabolism, which allowed for a much larger amount of energy to be derived (some other species did the same with sulfur with a bit less benefit).

This increased energy is partly what drove the development of multicellular life by about 1 billion years ago. It should be pointed out that for 3.5 of the past 4.5 billion years that the Earth has existed, at most single celled life existed here.

Next, there was the snowball stage of the Earth, about 650 million years ago. Once again, this was a huge catastrophe for life on Earth. Most species at the time went extinct. After that, though, we started getting much larger animals and plants as the oxygen levels rose even further. The 'Cambrian explosion' is one of the consequences of this rise.

Then, at the end of the Paleozoic era, about 250 million years ago, the supercontinent of Pangea started to break up. This lead to another catastrophe for life on Earth with about 98% of species at the time going extinct.

Humans appeared far less than 1 million years ago (1-300,000 years) and we gained the technology for agriculture about 10,000 years ago. We learned how to control radio waves about 100 years ago, discovered nuclear power about 80 years ago, and figured out computers over the last 60 years or so.

So, to get here, life had to go through *at least* 3 major catastrophes that almost eliminated it. This suggests that getting to multicellular life is not an easy thing. So, while life (bacterial, anaerobic) might well be common, multicellular life may well be very rare. Even though there are hundreds of billions of stars in our galaxy, this might well mean that 'advanced life' (meaning multicellular life) might not be common at all.

Once again, the human species is quite young. We have been around for 1-300,000 years. But we have only done things that could be picked up by other planets in the last 100 years or so. Even then, the amount of power used was low enough that detection even at a few tens of light years would be very difficult.

Now for the difficult part. How much longer do we really think that the human species will survive? Given the multitude of ways we have already pushed ourselves to the brink of disaster, I would be very hesitant to say about 1000 years and I would be shocked at another 10,000 years.

So, suppose that technological species are rare and short lived. The likelihood we would detect another one is very low simply because the chances of overlap in time would be so low. A mere 10,000 years is an instant on the cosmological scale. If technological species kill themselves on that time scale, we may very well be alone in our galaxy (even if such species occur with some frequency).

Unfortunately, I find this the most likely resolution of the Fermi paradox: species such as ours tend to destroy themselves 'quickly' after gaining technology that could do so. This would be accentuated by any attempts to reach other stars simply because the economics of stellar travel would be ruinous to most civilizations. Trying to obtain the energy and resources required to get a ship with a few hundred individuals to, say, 5% of the speed of light would be more than we could reasonably manage with our politics and social issues. I suspect the same would be true elsewhere. And, even if a ship or two did manage to get to another star system, the chances of survival are small and, again, another 10,000 years and the same issues would appear.

Now, with enough galaxies, it is possible one or two species manage to overcome this hurdle. But I suspect the simple problems of interstellar travel and communication mean that this is very rare (we certainly have not managed it. In fact, we haven't even managed to get a human on the nearest planets to us).

We may not be the first, but we might still be alone.

 

[Polymath257]

Yep, At 20% c the relative mass is about 3% bigger than the rest mass.

Yes. And to get an ounce of mass to that speed would take the energy equivalent of the nuclear weapon that destroyed Hiroshima.

 

[Heyo]

The real problem is that the energy involved increases as the square of the velocity (actually a bit more of you consider relativistic effects). That energy has to come from somewhere. If you use fusion, you still need to carry the fuels prior to use.

That's the nice thing about fusion, you don't. The interstellar medium is full of hydrogen and most of it is a plasma, i.e. you can collect it with a magnet. So, the rocket equation doesn't limit fusion engines.

 

[Heyo]

The problem is that we only have one example of a place where life exists: the Earth. So we don't fully understand what is required to get life formed and what else it takes to get to an 'advanced' species. Going along with the question, I will assume that humans qualify as an advanced species.

So, based on what we know, what can we say about the development of life? Well, for the first thing, the basic elements (carbon, oxygen, nitrogen, sulfur, phosphorus, etc) are formed in stars at the end of their lives or in supernovae. This means that an entire stellar cycle has to have happened before life has any chance of arising. The universe is about 13.7 billion years old, and stellar cycles of the required sort can happen 'relatively fast' because the stars involved are large and go through their cycles quickly. So, we need a few billion years there.

The sun and Earth are about 4.5 billion years old, so they were formed about 9 billion years after the current expansion phase began. That is plenty of time to form the heavier elements required for life and, perhaps, there could have been life forming a few billion years before the Earth formed.

From evidence on the Earth (again, caution because of only one example), life got started easily (by about 3.8 billion years ago) and so we might expect anaerobic bacterial life to be common in the universe. ALL life on Earth was of this form until about 2 billion years ago, during the great oxygenation event. In other words, for 1.8 billion years only anaerobic bacteria lived on Earth.

During the oxygenation event, the *poisonous* oxygen was released into the atmosphere, leading to many species going extinct. This was the first major catastrophe for life on Earth (that we know about---maybe the transition from RNA to DNA was equally catastrophic). Those species that survived were able to use oxygen in their metabolism, which allowed for a much larger amount of energy to be derived (some other species did the same with sulfur with a bit less benefit).

This increased energy is partly what drove the development of multicellular life by about 1 billion years ago. It should be pointed out that for 3.5 of the past 4.5 billion years that the Earth has existed, at most single celled life existed here.

Next, there was the snowball stage of the Earth, about 650 million years ago. Once again, this was a huge catastrophe for life on Earth. Most species at the time went extinct. After that, though, we started getting much larger animals and plants as the oxygen levels rose even further. The 'Cambrian explosion' is one of the consequences of this rise.

Then, at the end of the Paleozoic era, about 250 million years ago, the supercontinent of Pangea started to break up. This lead to another catastrophe for life on Earth with about 98% of species at the time going extinct.

Humans appeared far less than 1 million years ago (1-300,000 years) and we gained the technology for agriculture about 10,000 years ago. We learned how to control radio waves about 100 years ago, discovered nuclear power about 80 years ago, and figured out computers over the last 60 years or so.

So, to get here, life had to go through *at least* 3 major catastrophes that almost eliminated it. This suggests that getting to multicellular life is not an easy thing. So, while life (bacterial, anaerobic) might well be common, multicellular life may well be very rare. Even though there are hundreds of billions of stars in our galaxy, this might well mean that 'advanced life' (meaning multicellular life) might not be common at all.

Once again, the human species is quite young. We have been around for 1-300,000 years. But we have only done things that could be picked up by other planets in the last 100 years or so. Even then, the amount of power used was low enough that detection even at a few tens of light years would be very difficult.

Now for the difficult part. How much longer do we really think that the human species will survive? Given the multitude of ways we have already pushed ourselves to the brink of disaster, I would be very hesitant to say about 1000 years and I would be shocked at another 10,000 years.

So, suppose that technological species are rare and short lived. The likelihood we would detect another one is very low simply because the chances of overlap in time would be so low. A mere 10,000 years is an instant on the cosmological scale. If technological species kill themselves on that time scale, we may very well be alone in our galaxy (even if such species occur with some frequency).

Unfortunately, I find this the most likely resolution of the Fermi paradox: species such as ours tend to destroy themselves 'quickly' after gaining technology that could do so. This would be accentuated by any attempts to reach other stars simply because the economics of stellar travel would be ruinous to most civilizations. Trying to obtain the energy and resources required to get a ship with a few hundred individuals to, say, 5% of the speed of light would be more than we could reasonably manage with our politics and social issues. I suspect the same would be true elsewhere. And, even if a ship or two did manage to get to another star system, the chances of survival are small and, again, another 10,000 years and the same issues would appear.

Now, with enough galaxies, it is possible one or two species manage to overcome this hurdle. But I suspect the simple problems of interstellar travel and communication mean that this is very rare (we certainly have not managed it. In fact, we haven't even managed to get a human on the nearest planets to us).

We may not be the first, but we might still be alone.

:winner:

 

[Subduction Zone]

That's the nice thing about fusion, you don't. The interstellar medium is full of hydrogen and most of it is a plasma, i.e. you can collect it with a magnet. So, the rocket equation doesn't limit fusion engines.

You just have to find those magnetic monopoles.

Bussard ramjet - Wikipedia

en.wikipedia.org

 

[Twilight Hue]

The Fermi Paradox is the thought that there is a high likelihood of extraterrestrial existence, yet there is no evidence for any.

What are your solutions to this paradox? I have this in Science and Religion because I'm interested in religious takes as well as scientific ones.

The idea that trips me out the most is that we are perhaps the first advanced species in the universe. The first. Well, some species has to be the first. Maybe it's actually us. What a grand and most unique opportunity this offers humanity.

Another theory I heard was that advanced alien civilizations know to stay in the dark, for fear of being wiped out by other civilizations.

What do you think?

I go with the thought that advanced civilizations eventually destroy themselves, which suggests technology is limited in other areas of the universe as we are.

 

[Twilight Hue]

Another thought via Scientific American on the matter.

The Search for Extraterrestrial Life as We Don't Know It

Scientists are abandoning conventional thinking to search for extraterrestrial creatures that bear little resemblance to Earthlings

www.scientificamerican.com

 

[excreationist]

Now for the difficult part. How much longer do we really think that the human species will survive? Given the multitude of ways we have already pushed ourselves to the brink of disaster, I would be very hesitant to say about 1000 years and I would be shocked at another 10,000 years.

How would every single human be wiped out? Would there be nuclear weapons that kill every single human including in the most remote places? What if some are in underground bunkers? How would all of those people be eliminated?
People like Elon Musk want there to be a million people on Mars ASAP precisely because of the possibility that everyone on the Earth could be wiped out. Then I think some people from Mars could repopulate the Earth - even if they have to wear space suits when they are outside. There could be a large number of people on Mars within a few centuries.
There is a big difference between "to the brink of disaster" and the complete elimination of humans.
I think nearly any catastrophe that can be anticipated could be survived - provided you have a few centuries to start a large colony on Mars....
If people are able to upload their minds into computers then it would be even harder to wipe everyone out... (if the minds weren't centralised)
If the machines kill all of the humans then the machines would be an intelligent "species" that might want to take over the universe.

 

[Heyo]

How would every single human be wiped out? Would there be nuclear weapons that kill every single human including in the most remote places? What if some are in underground bunkers? How would all of those people be eliminated?

It's not about individual humans, it's about human culture. When we get bombed back into the 18th century. we cease to send detectable electromagnetic waves. It is as if we were not there.

People like Elon Musk want there to be a million people on Mars ASAP precisely because of the possibility that everyone on the Earth could be wiped out. Then I think some people from Mars could repopulate the Earth - even if they have to wear space suits when they are outside. There could be a large number of people on Mars within a few centuries.

Nonsense. Why would anyone descend into a new gravity well right after having escaped from Earth's. There is nothing on Mars that's interesting for a living human except resources. And they are cheaper on the Moon and the asteroids.
Space habitats are the way to go. The rotation gives you all the (artificial) gravity you want and being in space gives you access to the Sun's energy 24/7. The building costs won't exceed those of planetary habitats by much as you have to have sealed, pressurized, radiation shielded space anyway. And if you detect a big meteoroid in time, you can simply move to the side.

There is a big difference between "to the brink of disaster" and the complete elimination of humans.
I think nearly any catastrophe that can be anticipated could be survived - provided you have a few centuries to start a large colony on Mars....
If people are able to upload their minds into computers then it would be even harder to wipe everyone out... (if the minds weren't centralised)
If the machines kill all of the humans then the machines would be an intelligent "species" that might want to take over the universe.

It all depends on whether we can make the step into space before climate change (or an other, unforeseen catastrophe) gets us so hard that we no longer have the free resources to do so.