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  1. #1
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    Default The Fermi Paradox

    ...or The Great Silence

    First we need to gain our bearings and get some perspective.

    Our galaxy, a spiral formation of hundreds of billions of stars which we’ve named the Milky Way because of how it stretches across the night sky, is estimated to be somewhere between 13 and 14 billion years old.


    Our home stellar system revolves around a G2 star we call Sol that is approximately 4.6 billion years old. Sol system occupies the Orion arm of the Milky Way’s spiral, about 27,000 light years from the supermassive black hole thought to dwell in the galactic hub. If the hub is downtown, we’re in the suburbs.


    Estimates of the diameter of the Milky Way vary but no one’s going to get too upset if I go with 100,000 light years. As for the number of stars in our galaxy, estimates vary from 100 billion to 400 billion; let’s be conservative and settle on 100 billion. They all rotate around the galactic hub, making a circuit ever 240 million years, while the galaxy itself is racing through intergalactic space at something like 1.3 million miles an hour.

    Of those 100 billion stars, 75% are red dwarves. Sol, however, is a rarer type, one of the so-called yellow dwarves, or G-class stars, that make up 4 to 5% of the 100 billion. Astronomers estimate that the Milky Way contains over 40 billion Earth-size planets occupying the Goldilocks
    zones around red and yellow dwarf stars.

    For those not familiar with the terms, Earth-size mean 0.5 to 2.0 times the Earth’s diameter. The Goldilocks zone – also known as the Habitable Zone – is the area around any given star where water can maintain a liquid state. There’s also something called the GHZ – the Galactic Habitable Zone, which is estimated to span roughly 22,000 to 30,000 light years from the hub. Earth resides in the Milky Way’s GHZ.


    So, to sum up: current conservative estimates are for 40 billion habitable Earth-size planets in the Milky way, most of them circling red dwarves but 2 billion or so circling yellow dwarves.

    Think about that: 40 billion potential Earths circling red dwarves, 2 billion circling Sol-type stars. And that’s based on just a hundred billion stars in the Milky Way – it’s probably twice that number, maybe three times. And most of those stars are much older than Sol – up to 4 billion years older – giving life on them hundreds of millions, maybe even a billion more years to develop. (Consider that the earliest Australopithicus appeared just 4 million years ago.)

    Which leads to Fermi’s question: Where is everyone?

    Enrico Fermi, the genius Italian physicist, was one of the so-called fathers of the atom bomb. The paradox of his question, posed in 1950, remains unanswered. With billions of habitable planets in our galaxy (I’m not going to touch the unthinkable number of planets in all the billions of galaxies throughout the universe), so many of them older than ours, why haven’t we found a trace of sapient life anywhere else? (Notice I’m using “sapient” instead of “intelligent” because intelligence is vulnerable to interpretation and the inevitable wisecracks.)

    Human civilization started in Mesopotamia about 8 thousand years ago. Alien civilizations around older stars could easily be millions of years old. Even at non-relativistic speeds, that’s plenty of time to colonize the habitable planets in their stellar neighborhood and far beyond.

    We’ve been listening for interstellar soundbites via the various SETI (Search for Extra-Terrestrial Intelligence) groups since the early 1980s, but not hearing a thing. It’s called the Great Silence, and it leads to an inevitable question: Are we alone in our sapience?

    In what might be called the Great Noise, humanity has been beaming electromagnetic waves since the invention of radio. Those waves escape into space and travel at the speed of light in all directions. Estimates say that once they reach the 60-light-year mark (which they have) they won’t be distinguishable from background noise. But we’re talking a sphere 120 light years in diameter. And since the 80s we’ve been deliberately beaming messages out there. Any being passing through that space would hear something.

    And yet…nothing. Like one of my fave Beatles songs: No Reply.

    A slew of explanations has been offered. The most simplistic: We are the only sapient lifeform in the universe because a Supreme Being (spin the wheel and take your pick) created the universe just for us. This is the obvious favorite of many religions.

    So many other theories: We are under quarantine until we mature, we are an experiment and under observation, we simply aren’t that interesting, no one has come close enough to be aware of us, we were discovered millennia ago and are viewed as a sort of preserve to be observed and toyed with. (That's the Fortean outlook: “The Earth is a farm. We are someone else’s property.”)

    What do I think? Haven’t a clue. I’m perfectly happy with saying I don’t know who or what’s out there and what they’re up to if they are. If pressed, I’ll use Occam’s Razor and say they simply haven’t got around to us yet.

    And maybe that’s a good thing – not noticing us. Because as Stephen Hawking has said, contact with extraterrestrials carries a significant probability of a bad outcome. To quote the man, the encounter "might be a bit like the original inhabitants of America meeting Columbus. I don't think they were better off for it."

    So, have I laid all this before you just to say I don’t know? Truth is, I did it for me. To have my next novel’s central conceit – its maguffin, if you will – make sense to me and, by extension, to the reader, I need to reference the Fermi Paradox. This post is a way of assembling facts and theories and organizing my thoughts –
    and giving your brains something to consider while I'm at it.

    How do I reference the Paradox? A central character believes that sapience is so rare in the universe that it draws attention.

    Isn’t that a creepy thought? Remember the second part of the Chinese curse? May you come to the attention of one in authority. That has always given me a chill. What if we are under the scrutiny of (to quote Wells) “intellects vast, cool and unsympathetic”? I am not a Fortean, but it’s a nifty premise to play with in a novel – not center stage, but lurking in the background.

    Keep watching the skies – and this space. I’ll come back to all that later.


    Last edited by fpw; 08-25-2015 at 08:16 AM.
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  2. #2
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    We haven't heard anything because Cthulhu is still dreaming in R'lyeh. We'll hear something from him when the stars are right.

    Had to say that in honor of HPL's upcoming birthday and the NecronomiCon. Sounds like you are already in the groove for a good panel discussion or two.

    But seriously that is a great question. Where the heck is everyone?

    And when are we all going to get to read this new novel?

  3. #3
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    Quote Originally Posted by DaveStrorm View Post
    And when are we all going to get to read this new novel?
    Next year -- summer, most likely.
    FPWHidden Content
    "It means 'Ask the next question.' Ask the next question, and the one that follows that, and the one that follows that. It's the symbol of everything humanity has ever created." Theodore Sturgeon.

  4. #4
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    The other reason may be because of the energy costs, Paul.

    At between 70 and 80 light years, even using a full-blown conversion engine that can come close to attaining the speed of light (and good luck finding materials that can handle that kind of stress), it would still be a minimum of a 160 year round trip to go from point A to point B.

    We've only been broadcasting into the ether for about 120 years, which means the first neighbors to hear the noise pollution won't be coming around to complain for about another 20 years or so. They may also be totally unaware of radio signals, because they have a different biology.

    So, Fermi's Paradox, while intriguing, is basically ethnocentric. Sentient life doesn't have to be bipedal, upright, and have the same spectrum sensitivity that we have. For all we know, there may be other sentient life here on Earth that we have not yet discovered.

    The other thing about the energy costs is the return on investment. Even if you COULD visit Ougadougou or Timbuktu, why would you want to if Paris is easier to get to?
    "You have the right to remain silent. If you choose to waive this right, I may have to kill you in self-defense because you're boring me to death."

  5. #5
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    (crossposted) But if we're dealing with any other civilizations at all, the potential range of their ages spans into the millions of years. Spacefaring civilizations would be less prone to stagnation and would be relatively immune to a single species-ending event. They'd also have figured out a means of propulsion that is, if not relativistic, at least realistic in the economic sense.
    FPWHidden Content
    "It means 'Ask the next question.' Ask the next question, and the one that follows that, and the one that follows that. It's the symbol of everything humanity has ever created." Theodore Sturgeon.

  6. #6

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    I'm not trying to nitpick, but it's "the Goldilocks zone" not "the Cinderella zone". It's because that area is not to "hot"and not to "cold", but just "right". Other than that, it's a great post!

  7. #7

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    Quote Originally Posted by mad4tunes View Post
    The other reason may be because of the energy costs, Paul.

    At between 70 and 80 light years, even using a full-blown conversion engine that can come close to attaining the speed of light (and good luck finding materials that can handle that kind of stress), it would still be a minimum of a 160 year round trip to go from point A to point B.



    The other thing about the energy costs is the return on investment. Even if you COULD visit Ougadougou or Timbuktu, why would you want to if Paris is easier to get to?
    Scientists now believe that an electromagnetic propulsion drive is possible. They wrote it off 15 years ago because it defied the laws of physics.

    Projected times using it are...

    The Moon...4 hours.
    Mars.....70 days.
    Pluto... about 18 months

    Alpha Centauri... 100 years.

    To put that into perspective, the New Horizon spacecraft took 9 years to reach Pluto.

  8. #8
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    Quote Originally Posted by Logan View Post
    I'm not trying to nitpick, but it's "the Goldilocks zone" not "the Cinderella zone". It's because that area is not to "hot"and not to "cold", but just "right". Other than that, it's a great post!
    I believe I've heard both. But thinking about it, Goldilocks makes more sense. Thanks for the heads up. I've changed it.
    FPWHidden Content
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  9. #9
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    Another treatment of this was done in Stephen Baxter's novel "Manifold:Time" (first in a series of three), with much the same answers. I've always figured that we're one of the first sapient species in this galaxy - or at least in our observable 'neck of the woods'. It's possible that a civilization on the other side of the galaxy could be hidden by the clutter surrounding hub, as well.

    (Couldn't help but have Eric Idle's "Galaxy Song run through my head as I read through this thread...)

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