Solutions to the Fermi Paradox

[Moar Boosters]

Honestly, why should we be hearing from other life-forms if there's so much of it? Most radio signals, as Cirocco mentioned, as well as most other kinds of signal, with few exceptions drop off into the cosmic background noise after around 2 light-years with our current technology, well before reaching any other stars. And as technology improves, our radio signals get fainter and weaker, because we can afford to transmit more, with less. I think that more advanced technological sapient life-forms could easily be invisible just because they don't want to pay the power bill to transmit signals around the galaxy.

Sounds about right. You could put somebody on earth from 300 years ago, and they might wonder why we don't communicate with each other because nobody is climbing up mountains and blowing a big horn. Even as a child I've always been fascinated by how "messy" radio is as a communication device. If aliens are advanced enough to master faster than light travel, I'm sure they'll have a way of sending information to the intended recipient without spamming the entire universe.

I guess that brings up an interesting idea.

Our first contact could well be an offer for magical tablets which promise to increase the size of our jaggons.

[Technical Ben]

Because they too, as we are presently, are banging their heads against the speed of light limit.

It's not a problem to the Fermi Paradox. Even a fly could be communicating with us in the time it's had.

There is a chance we are the first/only life there is. Why only consider the chance we are the middle of many, the last, and not also consider we are the first?

[Bill Phil]

Because, 10E9 years, or more.

[GoSlash27]

Eventually, humans will live alongside other intelligent beings in the galaxy, with trade going to multiple worlds. Before that day can come, we must put down our weapons, our hate and distrust and reservations, and greet our fellow man with open arms, embracing him the same way we embrace our differences. We are like children, and we must grow up before we can sit with the adults.

This flies in the face of everything we know about life in general and human nature in particular.

We haven't heard from any other civilizations because.... well, why *would* we? Radio signals diminish too rapidly to be detected over meaningful distances.

And really... that's probably a good thing. Any intelligent life we're likely to encounter is liable to be as mistrustful and violent as we are.

Best,

-Slashy

[78stonewobble]

Only very advanced and dedicated alien civilisations within a miniscule area of the milkyway could possibly have picked us up and if they're limited to FTL a message could be on it's way, it just haven't arrived yet. Unlikely...

The universe and galaxies had some maturing to do before life became possible. First, because the components necessary for life had to be produced and spread in decent enough ratios and secondly because active galactic nuclei seems more prolific in the early universe and life probably can't develop or survive that.

My personal and uneducated guestimation?

Life is quite rare. Not unique to our planet, but just quite rare... I'd say between 1.000 to 10.000 places in our galaxy.

Intelligent life is even more rare, because it needs the right conditions for life even longer and thus over time faces bigger threats. At most 10-50 in the galaxy.

FTL is probably not possible ( sadly and makes this a boringverse ), which would make civilisations very isolated.

Interstellar travel is so prohibitively expensive that organic species probably never do that too much. They might... if ambitious, establish a few backups here and there, but it will be slow and be massive undertakings each time.

Even artificial intelligences might hit a brick wall in intelligence due to lightspeed and the ability to densify information... Plus I presume they would have an easy time of limiting population growth compaired to instinct based organics.

[Dispatcher]

My uncle's pet rock has been trying to communicate with him for several decades. The problem is, our metabolism and the rock's metabolism are too divergent to allow perception of any communication by one or the other.

[PakledHostage]

Our first contact could well be an offer for magical tablets which promise to increase the size of our jaggons.

Or it could be something akin to an image that Magnemoe posted in an earlier thread about first contact:

[Jovus]

My personal favorite answer: we have heard from other civilizations. And no, I'm not talking about little green men or cow-molesters. Rather, many of the slightly-exotic pulsars we see (and/or other highly regular emission sources) are beacons from a Kardashev Type II civilization.

Not that I'm convinced it's true. There's no evidence either way for any supposition.

[Bill Phil]

Chances are, that ET probes have explored the solar system, and then destroyed themselves a la Galileo.

[cicatrix]

A type III civilization (if it exists) would find very little practical use in remaining material. Look at all these gamma radiaton events, supernovaes and other cosmic cataclysms. What if we DO see them communicating with each other but in a way we would not comprehend. I cannot imagine harnessing the energy of a star, but a whole galaxy?! We're not living in the same scale I think. A human lifespan is a blink of an eye for them. Record your speech and slow it down a million times then listen. What do you hear? Nothing!

Every second billions of neutrinoes fly through your body and we do not care. There is dark matter and dark energy we cannot even detect. Who knows? Maybe they ARE among us.

Edited January 21, 2015 by cicatrix

[magnemoe]

Or it could be something akin to an image that Magnemoe posted in an earlier thread about first contact:

http://fc07.deviantart.net/fs70/f/2012/177/5/4/first_contact_5_by_olsen1a-d54w8yu.jpg

Thanks And yes I see it as an pretty realistic scenario. It would be very hard to spot hunter gatherers even from orbit.

[KerikBalm]

Life, from everything we've seen, and from inate principles, will expand to fill every available niche.

Those that propgate the most become more common, those that don't become less common.

With fusion power (not even bussard ramjets, antimatter, or warp drives, or Q thrusters [the last two are likely not possible]), and the same mass fraction as a Saturn V, one could traverse the galaxy at 0.2C

The galaxy has a diameter of 100,000 light years. A civilization that acheives fusion powered spaceflight could therefore cross the galaxy in 500,000 years.... lets double that time to allow half a million years for outposts to be built up into self sustaining industries before the next wave.

1 million years between the first civilization with fusion power, and spreading across the entire galaxy.

Life on Earth has been here for 4,000 million years. Some planets would have formed a few billion years before us, some are just forming now. Given when heavy elements first became abundant enough for life as we know it, we can expect by these (IMO too optimistic) drake equations that there was life 7,000 million years ago.

One Earth, since the permian, all the biological innovations needed to produce humans were present (that was ~300 million years ago), a neocortex, high metabolic rates, terrestrial locomotion, woody plants to provide building materials and places to climb, 5 fingered limbs.... I see no reason that something human like couldn't have evolved in the Permian... 300 million years ago.

Yet between the appearance of the biological species that could presumably have fusion powered spaceflight (lets give them a few million years to evolve, as hominids took about that long), and complete colonization fothe galaxy, it should only be 5 million years.

Life on earth has been here for 4,000 million years, life in the galaxy likely more like 7,000 million years....

So why wasn't Earth colonized long long ago? It seems to me the only reason we are here, is that nothing else got here first. Either we have a chance at being the first, or there's a huge coincidence, and we happen to be in that 1 million year time frame (out of hundred to thousands of millions of years that it could have happened) where the first species is still expanding.

So, maybe life isn't that common, and maybe when it does happen, it rarely evolves intelligence.

And when it evolves, perhaps it destroys itself, as we are constantly in danger of doing.

So lets not destroy our environment.

Lets have a concerted effort to have fusion power.

The galaxy is ours for the taking if we just get our heads out of our butts.

[Streetwind]

Thanks And yes I see it as an pretty realistic scenario. It would be very hard to spot hunter gatherers even from orbit.

A common misconception.

In fact, if we limit ourselves to "life as we know it" - i.e. carbon-based - there are very clear indicators that a planet hosts life that can be spotted from well beyond orbit. We can already today measure the atmospheric composition of exoplanets dozens to hundreds of lightyears away with ground-based telescopes with enough precision to completely rule out carbon-based life, for instance - simply because the presence of such life would not only require a certain atmospheric composition, but also change that composition in a certain, very predictable pattern just by being there. It is expected that the first discovery of an intelligent species comparable to ourselves would come not from its radio signals, but rather from the way their presence alters the atmosphere of their home planet. But even a teeming microbial ecosystem can be detected this way.

The problem of telling apart a sentient hunter-gatherer species from lower level lifeforms is a real one, I'll admit. But the presence or absence of life per se is fairly doable from afar. Also, it should be noted that the Fermi Paradox deals with communicating civilizations only (i.e. well beyond the hunter-gatherer level).

And then there's always the thing about life in forms we cannot imagine right now. We obviously can't spot those quite as readily. But we can still be on the lookout for unusual observations.

Edited January 21, 2015 by Streetwind

[1of6Billion]

Here's our 'radio bubble'. Any neighbouring civilisation is just too far away, even if you plug the most optimistic numbers in the Drake Equation.

[KerBlam]

[magnemoe]

A common misconception.

In fact, if we limit ourselves to "life as we know it" - i.e. carbon-based - there are very clear indicators that a planet hosts life that can be spotted from well beyond orbit. We can already today measure the atmospheric composition of exoplanets dozens to hundreds of lightyears away with ground-based telescopes with enough precision to completely rule out carbon-based life, for instance - simply because the presence of such life would not only require a certain atmospheric composition, but also change that composition in a certain, very predictable pattern just by being there. It is expected that the first discovery of an intelligent species comparable to ourselves would come not from its radio signals, but rather from the way their presence alters the atmosphere of their home planet. But even a teeming microbial ecosystem can be detected this way.

The problem of telling apart a sentient hunter-gatherer species from lower level lifeforms is a real one, I'll admit. But the presence or absence of life per se is fairly doable from afar. Also, it should be noted that the Fermi Paradox deals with communicating civilizations only (i.e. well beyond the hunter-gatherer level).

And then there's always the thing about life in forms we cannot imagine right now. We obviously can't spot those quite as readily. But we can still be on the lookout for unusual observations.

I agree, an oxygen atmosphere can be detected far away, you can detect oxygen in earth atmosphere much longer distance than radio noise even if we had sent at the same level for hundreds of years.

If you managed to actual take an picture of the planet you would probably see if it was decent with plant life too simply by looking at large scale color changes who could not be caused by snow.

The image was kind of an joke on first contacts, part in that if we discover aliens they would either be stone age or more advanced than us, would require serious luck to hit inside the 5000 year span between the two states.

[*Aqua*]

That always bugs me. People always assume that humans are horrible, crude, honorless, violent monstrosities that are below every other life in existence.

Evolution rewards lifeforms for being forceful. They are more likely to survive the dangers of their enviroment.

We can assume that there's always some sort of evolution going on where ever life exists.

Btw, "horrible, crude, honorless, violent monstrosities" are just opinions of some people which can change over time. Nature doesn't know morals and ethics. And there's no reason to believe aliens know about them too. They could have a complete different mindset (if they have something we call mindset).

---

Why only consider the chance we are the middle of many, the last, and not also consider we are the first?

Because, 10E9 years, or more.

@Bill

That's no answer to Ben's question. Probabilities don't tell you when or if an event comes true in a given period of time. It could be that we're the last intelligent lifeform in the universe which will ever evolve. It could also be that we're the first one. And it could be that we'll be the only ones which will ever exist.

[Bill Phil]

My statement is an answer, pointing out that the likelihood of is being the first is low, and the same for the last. Billions of years, is a looooooong time, anything can happen in one billion years, and there's been ~14 billion years for that to happen.

[Rakaydos]

My statement is an answer, pointing out that the likelihood of is being the first is low, and the same for the last. Billions of years, is a looooooong time, anything can happen in one billion years, and there's been ~14 billion years for that to happen.

Except for a majority of that time, it simply was not possible for high tech life to develop.

"Population II, or metal-poor stars, are those with relatively little metal. The idea of a relatively small amount must be kept in perspective as even metal-rich astronomical objects contain low percentages of any element other than hydrogen or helium; metals constitute only a tiny percentage of the overall chemical makeup of the Universe, even 13.8 billion years after the Big Bang. However, metal-poor objects are even more primitive. These objects formed during an earlier time of the Universe. Intermediate Population I stars are common in the bulge near the centre of our galaxy; whereas Population II stars found in the galactic halo are older and thus more metal-poor. Globular clusters also contain high numbers of Population II stars.[24] It is believed that Population II stars created all the other elements in the periodic table, except the more unstable ones. An interesting characteristic of Population II stars is that despite their lower overall metallicity, they often have a higher ratio of alpha elements (O, Si, Ne, etc.) relative to Fe as compared to Population I stars; current theory suggests this is the result of Type II supernovae being more important contributors to the interstellar medium at the time of their formation, whereas Type Ia supernovae metal enrichment came later in the Universe's evolution.[25]"

Thus the capability of technological life to develop (heavy elements) begins in the galactic core and moves outward, and our solar sysem is on the outer edge of this band at the moment.

If we assume the galactic core is uninhabitable for some reason (high radiation from near stars and plentiful supernovae will do it) it is perfectly reasobable to assume we may be one of the first races to reach a technological level.

In addition...

According to recent studies, the Milky Way as well as Andromeda lie in what in the galaxy color–magnitude diagram is known as the green valley, a region populated by galaxies in transition from the blue cloud (galaxies actively forming new stars) to the red sequence (galaxies that lack star formation). Star-formation activity in green valley galaxies is slowing as they run out of star-forming gas in the interstellar medium. In simulated galaxies with similar properties, star formation will typically have been extinguished within about five billion years from now, even accounting for the expected, short-term increase in the rate of star formation due to the collision between both the Milky Way and the Andromeda Galaxy.[141] In fact, measurements of other galaxies similar to the Milky Way suggest it is among the reddest and brightest spiral galaxies that are still forming new stars and it is just slightly bluer than the bluest red sequence galaxies.[142]

so there arnt going to be too many younger races either.

[GoSlash27]

Here's our 'radio bubble'. Any neighbouring civilisation is just too far away, even if you plug the most optimistic numbers in the Drake Equation.

http://jackadam.net/misc/radio_broadcasts/radio_broadcasts.jpg

Aye. There's only so many G class stars within 50 LY of us (a little over 50) and most of them don't have planets.

Of those that do, very few have planets in their "goldilocks zone" and of those that do, none of them are Earth sized.

Probably life on several of them, but the odds of intelligent life in our neighborhood is about nil despite it being statistically certain on a larger scale.

Best,

-Slashy

[Scotius]

It's entirely possible that very advanced civilisations are all around us. But we don't know what to look for. Consider an uncontacted, primitive hunter-gatherer tribe living deep in the Amazonian jungle, hundreds of kilometers from any "civilised" place with electricity, wifi access etc. They might believe they are only humans in existence, not realising there are terabytes worth of data passing through their bodies on electromagnetic waves. And thousands of other humans travelling just couple of kilometers above their heads, inside the airplanes our natives can't even imagine. That is difference of about 2000 years of advancement. A civilisation 2000 years older than ours, will be literally and figuratively speaking above our heads too. And they might be watching us right now From afar - not interfering from fear of destroying our fragile culture. Just like Earthborn scientists keep an eye on primitive tribes still hanging on in isolated parts of our planet.

[magnemoe]

Aye. There's only so many G class stars within 50 LY of us (a little over 50) and most of them don't have planets.

Of those that do, very few have planets in their "goldilocks zone" and of those that do, none of them are Earth sized.

Probably life on several of them, but the odds of intelligent life in our neighborhood is about nil despite it being statistically certain on a larger scale.

Best,

-Slashy

This distance between suitable planets might be an reason for no galactic empires too, distances is too long even the most dedicated civilisations stop spreading out then they get gulfs with too far to the next stars and they already have some colonies.

[PakledHostage]

Probably life on several of them, but the odds of intelligent life in our neighborhood is about nil despite it being statistically certain on a larger scale.

I'm inclined to agree. The trouble with the Drake equation is that it is only as good as the estimates that feed it. I think people often vastly overestimate the number of technologically advanced species. When you consider all of the lucky breaks that we've had that have allowed us to develop to our present level of technology, it isn't unreasonable to consider ourselves to be exceedingly rare. Consider, for example, the effect that a close encounter with another star or massive extra-solar planet would have on the orbits of planets around our Sun? Yet our planet's orbit has been stable for billions of years. Then there are cosmic killers like gamma ray bursts, asteroid/comet impacts, etc. Add super volcanoes and other climate shocks to that mix and it is a wonder we've made it this far.

It stands to reason that life is fairly common given the vastness of the universe, but I don't believe that intelligent life is equally so. Maybe there's only one civilization per galaxy on average? And what are the chances that such rare civilizations exist at the same time? The scale of the universe and the time horizons over which a civilization may exist (relative to the age of the universe) would effectively bar those civilizations from ever encountering each other.

[Duxwing]

Science-fiction speculation:

-Star Trek: Other civilizations exist and follow the Prime Directive of non-interference.

-Mass Effect: BioWare's fiction is horribly accurate and we are the first intelligent life arising after the last Reaper cycle.

-Star Wars: Other civilizations exist, use nigh-invisible power sources, and simply do not bother contacting us.

-Duxwing

[Bill Phil]

Aye. There's only so many G class stars within 50 LY of us (a little over 50) and most of them don't have planets.

Of those that do, very few have planets in their "goldilocks zone" and of those that do, none of them are Earth sized.

Probably life on several of them, but the odds of intelligent life in our neighborhood is about nil despite it being statistically certain on a larger scale.

Best,

-Slashy

Whose to say G class are the only ones with life? In fact, G type stars are pretty unstable, especially compared to K type stars, which can last dozens of billions of years.