Free Republic
Browse · Search
News/Activism
Topics · Post Article

Skip to comments.

Our Galaxy Should Be Teeming With Civilizations, But Where Are They?
Project Phoenix ^ | 25 Oct 01 | Seth Shostak

Posted on 10/25/2001 9:13:53 AM PDT by RightWhale

Is there obvious proof that we could be alone in the Galaxy? Enrico Fermi thought so -- and he was a pretty smart guy. Might he have been right?

It's been a hundred years since Fermi, an icon of physics, was born (and nearly a half-century since he died). He's best remembered for building a working atomic reactor in a squash court. But in 1950, Fermi made a seemingly innocuous lunchtime remark that has caught and held the attention of every SETI researcher since. (How many luncheon quips have you made with similar consequence?)

The remark came while Fermi was discussing with his mealtime mates the possibility that many sophisticated societies populate the Galaxy. They thought it reasonable to assume that we have a lot of cosmic company. But somewhere between one sentence and the next, Fermi's supple brain realized that if this was true, it implied something profound. If there are really a lot of alien societies, then some of them might have spread out.

Fermi realized that any civilization with a modest amount of rocket technology and an immodest amount of imperial incentive could rapidly colonize the entire Galaxy. Within ten million years, every star system could be brought under the wing of empire. Ten million years may sound long, but in fact it's quite short compared with the age of the Galaxy, which is roughly ten thousand million years. Colonization of the Milky Way should be a quick exercise.

So what Fermi immediately realized was that the aliens have had more than enough time to pepper the Galaxy with their presence. But looking around, he didn't see any clear indication that they're out and about. This prompted Fermi to ask what was (to him) an obvious question: "where is everybody?"

This sounds a bit silly at first. The fact that aliens don't seem to be walking our planet apparently implies that there are no extraterrestrials anywhere among the vast tracts of the Galaxy. Many researchers consider this to be a radical conclusion to draw from such a simple observation. Surely there is a straightforward explanation for what has become known as the Fermi Paradox. There must be some way to account for our apparent loneliness in a galaxy that we assume is filled with other clever beings.

A lot of folks have given this thought. The first thing they note is that the Fermi Paradox is a remarkably strong argument. You can quibble about the speed of alien spacecraft, and whether they can move at 1 percent of the speed of light or 10 percent of the speed of light. It doesn't matter. You can argue about how long it would take for a new star colony to spawn colonies of its own. It still doesn't matter. Any halfway reasonable assumption about how fast colonization could take place still ends up with time scales that are profoundly shorter than the age of the Galaxy. It's like having a heated discussion about whether Spanish ships of the 16th century could heave along at two knots or twenty. Either way they could speedily colonize the Americas.

Consequently, scientists in and out of the SETI community have conjured up other arguments to deal with the conflict between the idea that aliens should be everywhere and our failure (so far) to find them. In the 1980s, dozens of papers were published to address the Fermi Paradox. They considered technical and sociological arguments for why the aliens weren't hanging out nearby. Some even insisted that there was no paradox at all: the reason we don't see evidence of extraterrestrials is because there aren't any.

In our next column, we'll delve into some of the more ingenious musings of those who have tried to understand whether, apart from science fiction, galactic empires could really exist, and what implications this may have for SETI.


TOPICS: Culture/Society; Editorial; Extended News
KEYWORDS:
Navigation: use the links below to view more comments.
first previous 1-2021-4041-6061-80 ... 361-378 next last
To: adx
Why build an interstellar "empire" if you can't live long enough to enjoy it or even administer it?

I agree -- you either solve the problem of faster than light travel OR increase life span to virtual immortality to make a galactic empire feasible.

41 posted on 10/25/2001 9:55:44 AM PDT by justanotherfreeper
[ Post Reply | Private Reply | To 12 | View Replies]

To: jpl
Depends on your definition of "rapid". In terms of "Galactic Time", one galactic year is the time it takes for one revolution on its' axis.

Given the SF "sleeper ships" (i.e. top speed ~.2c), and the time it take humans to fill and develop a planet to the point where they can send out a wave of their own sleeper ships( several hundred to a few thousand years, your guess is just as good as mine . . .), you could fill the galaxy in a couple of million years: an eyeblink in astronomic terms.

42 posted on 10/25/2001 9:56:32 AM PDT by Salgak
[ Post Reply | Private Reply | To 13 | View Replies]

To: Senator Pardek
Sagan also said that we should be responsible and put up big billboards warning all potential visitors to enter at their own risk for we will eat them.

re where are they: Everywhere. Just cloaked. Duh!

43 posted on 10/25/2001 9:57:32 AM PDT by That Poppins Woman
[ Post Reply | Private Reply | To 38 | View Replies]

To: adx
Their race better have a VERY long lifespan then. Why build an interstellar "empire" if you can't live long enough to enjoy it or even administer it? A race could colonize other systems, but since communications and travel are limited by the speed of light at best, political organization of an interstellar "empire" would be very hard or outright impossible. Basically, each system would be its own independent political entity and cultural "petri dish" evolving independently from fellow members of their species in other systems.

One wouldn't have much of an empire, true, absent some faster-than-light technology, or magic, or something. A civilization might realize, however, that it is likely not alone in the galaxy. It might understand, too, that all it would take is one other civilization to start colonizing the galaxy for the whole place to be occupied. Rather than risk getting overrun by aliens, this civilization might figure it's better for it to start colonizing. And there we are.

44 posted on 10/25/2001 9:58:20 AM PDT by Timm
[ Post Reply | Private Reply | To 12 | View Replies]

To: justanotherfreeper
Worm holes.

Didn't you guys catch the Learning Channel's special -- Hyperspace?

45 posted on 10/25/2001 9:58:33 AM PDT by That Poppins Woman
[ Post Reply | Private Reply | To 41 | View Replies]

To: Senator Pardek
I truly doubt that man will ever reach the stars because of these facts

It doesn't even have to involve a huge destructive war. Just look at how the Vietnam war sucked all the resources and interest out of landing on the moon, and how WTC911 has converted the space program to military goals already. And that is without any actual crippling damage to the infrastructure. How can we possibly go to the stars when infants such as bin Laden are whining for attention all the time?

46 posted on 10/25/2001 10:00:59 AM PDT by RightWhale
[ Post Reply | Private Reply | To 38 | View Replies]

To: RightWhale
You mean, we're not only liviing in the boonies, but we also live in the middle of a STRIP MINE?
47 posted on 10/25/2001 10:06:43 AM PDT by Just another Joe
[ Post Reply | Private Reply | To 24 | View Replies]

To: RightWhale
Read Kings of the High Frontier by Victor Koman.

From the Author
(From his Prometheus Award acceptance speech, delivered in San Antonio, Texas, Labor day weekend, 1997) Kings of the High Frontier has been part of my life for as long as I have been a writer. When I was a kid, I marveled at the idea -- in Robert A. Heinlein's novels and such movies as Destination Moon and When Worlds Collide -- that private funding could get us into Space. As a child growing up with NASA's space program, I saw that it took a lot of people, facilities, and money to get one, two, or three men -- and I mean men -- into orbit or to the Moon. No families in Space, lost or otherwise.

There had to be a simpler way. Heinlein wouldn't have lied to me!

I stopped being a NASA fan when they canceled the Moon flights in December of 1972. And I became an enemy of NASA when Skylab -- a better space station than MIR would ever be -- was allowed to disintegrate into scrap.

I felt that I was not alone in this rage. I knew that there must have been others who loved Space but despised or even hated the space program. What if some of them, I thought, worked for NASA? What if they took their expertise with them into a sort of Space Underground? What if NASA tried to stop them? We've recently heard about the Mars Underground, but this idea occurred to me two decades ago.

In the summer of 1976, I started work on a novel entitled Hidden Millions. The title suggested the laundered money that might flow into such a venture, but also the millions of people in the counter-economy who might be involved knowingly or unknowingly in the effort.

Suffice it to say that my abilities as a writer back then were raw and I shelved the 80 pages of the manuscript to concentrate on projects more appropriate to my skills...

It was in 1985 that I began to research a novel called Huntress, but at that time The Jehovah Contract was about to be published in the US and I only made some mental notes.

Then Challenger fell. And you note that I say "fell" and not "exploded." As we now know, the tank ruptured, but the spacecraft was not incinerated.

Shock turned to sorrow and almost immediately to rage. The disaster had killed seven astronauts and destroyed one fourth of Earth's space fleet. I knew that -- by then -- the scales must have fallen from the eyes of others both outside and inside NASA. After a brief year's detour to write Solomon's Knife, I began on the Dante-esque journey that was Kings of the High Frontier.

48 posted on 10/25/2001 10:10:27 AM PDT by sendtoscott
[ Post Reply | Private Reply | To 46 | View Replies]

To: RightWhale; mlo
I doubt a galactic empire could exist due to the problems of communication and transport accross such huge distances

Agreed, totally. Even if the galaxy is uninhabited by other civilizations, when we finally get off this mudball and get out there, we will have to break up into separate self-rule entities. While we might spread out throughout the galaxy in a million years once we get moving, linkages to a central authority would be next to impossible.

I Find Your Lack Of Faith Disturbing...

49 posted on 10/25/2001 10:11:24 AM PDT by Darth Dan
[ Post Reply | Private Reply | To 14 | View Replies]

To: RadioAstronomer; longshadow; VadeRetro; Physicist; Junior; *crevo_list
Where are they?
50 posted on 10/25/2001 10:11:50 AM PDT by PatrickHenry
[ Post Reply | Private Reply | To 46 | View Replies]

To: RightWhale
Our Galaxy Should Be Teeming With Civilizations, But Where Are They?

The "should be" is based on faulty assumptions and bad use of odds. If the odds of one intelligent species is X, then the odds of it happening a second time are not 2X but XX. When you get to the level of "teeming", then you're dealing with odds that have long since passed both improbable and impossible. To get around this, people have said things like, "Well, given the right conditions, the spontaneous generation of life from non-living substrates and its evolution into a rational, intelligent, and technological species is inevitable." Yeah, well, given the given. However, the chances of obtaining those given conditions (which are not simply water, chemicals, energy, and lack of temperature extremes but an incredible series of fortuitous circumstances) for a single instance of spontaneous generation without even considering all those that would have to obtain in going from that to creatures like us, are vanishingly small. The chances of it happening again are simply too small even to be considered. Actually, they're so small that believing that another series of such chance happenings could pop up a "teeming" number of civilizations is more credulous that positing special creation.
51 posted on 10/25/2001 10:12:03 AM PDT by aruanan
[ Post Reply | Private Reply | To 1 | View Replies]

To: Salgak; RightWhale
At the current pace of our space program, I would settle for seeing a manned mission to Mars take place in my lifetime. :)
52 posted on 10/25/2001 10:12:38 AM PDT by jpl
[ Post Reply | Private Reply | To 42 | View Replies]

To: RightWhale
bump
53 posted on 10/25/2001 10:17:44 AM PDT by Pentagram
[ Post Reply | Private Reply | To 1 | View Replies]

To: aruanan
Didn't Sagan make a point similar to this shortly before he died?
54 posted on 10/25/2001 10:20:05 AM PDT by Leonine
[ Post Reply | Private Reply | To 51 | View Replies]

To: amordei
There are also some interesting theories about gravity being the wave/particle duality and that the speed of gravity is many times that of the speed of light.
55 posted on 10/25/2001 10:20:44 AM PDT by jammer
[ Post Reply | Private Reply | To 25 | View Replies]

To: RightWhale
It's like having a heated discussion about whether Spanish ships of the 16th century could heave along at two knots or twenty. Either way they could speedily colonize the Americas.

This is an intriguing article, not to be dismissed lightly. However, the grand distances involved in space do raise additional difficulties. Would Columbus have set sail knowing that it would be his grandchildren that would have arrived?

I read an interesting article about whether humans could endure the required isolation for a trip to Mars. The consensus among psychologists is that it would be very unlikely. Multiple that into years!

It's quite certain that we humans have something within us that draws us to investigate the unknown. What if it is that that is unique?

56 posted on 10/25/2001 10:21:33 AM PDT by FormerLib
[ Post Reply | Private Reply | To 1 | View Replies]

To: RightWhale
Be nice to the the govt come clean on this: see

www.disclosureproject.com

57 posted on 10/25/2001 10:25:48 AM PDT by JmyBryan
[ Post Reply | Private Reply | To 1 | View Replies]

To: justanotherfreeper
I agree -- you either solve the problem of faster than light travel OR increase life span to virtual immortality to make a galactic empire feasible.

Now that I think about it, there's two problems: communications and force projection.

1) Communication times will render political adminstration of any "interstellar empire" impossible. Why send petitions to a distant ruler when you won't receive a timely reply? The local head-honcho on site will have to have considerable autonomy simply because of the problem with communications. He/She/It won't be able to call for outside help or advice, since by the time a reply makes it out there, years have passed, rendering the reply irrelevant.

2) Force projection: Say our local head-honcho decides to take over his/her/its turf. What can the "emperor" do about it? Due to communications, it'll take years before the "emperor" knows what's even going on. It'll take some more time to put together a force (assuming the "emperor" is completely starkers) to track our honcho down and hang him/her/it for their treason. Then it takes even more years to actually travel to the colony to go repossess it. Odds are, the forces sent to quell the insurrection will get chopped to pieces since the colony's had all that time to prepare a suitable welcome to outsiders, and the expedition can't exactly call for swift reinforcements. Of course, they could simply annihilate every inhabited portion of the planet/system, and send word back that some new property (slightly radioactive, perhaps?) is available.

Not much of a scalable "force spectrum", if you get my drift. Either do nothing, or flatten everything, with no in-between option like invasion and occupation.

Of course, biological, social, and political factors might mitigate this somewhat, but the problems only get worse with distance. End result is that a species may go hog-wild colonizing everything in sight, but no political organization will be in charge of anything beyond its own star system.

Since no political organization will benefit that much by sending off a lot of their loyal/troublesome citizens/subjects off into the void (it'd be simpler just to execute the dissidents), who else can do it? I believe that the only people that would have the motivation to leave everything they know behind and head off to parts unknown are those that have nothing to gain by staying home. Those dissident types (either political, religious, or those in any persecuted minority) may be the ones who have the reason to get away, but they probably wouldn't be able to pull it off unless they either got major backing or "acquired" the means to leave home.

As I said before, probably every civilization eventually evolves Democrats to hobble the rest of the population. :)

58 posted on 10/25/2001 10:26:01 AM PDT by adx
[ Post Reply | Private Reply | To 41 | View Replies]

To: aruanan
The Birth of the Drake Equation.
The Drake Equation,.
What is the Drake Equation?.
Drake Equation. (Plug in your estimates.)
59 posted on 10/25/2001 10:27:23 AM PDT by PatrickHenry
[ Post Reply | Private Reply | To 51 | View Replies]

To: aruanan
So are we the statistical fluke that proves the rule?
Or were we seeded by another culture and left to grow?
60 posted on 10/25/2001 10:27:29 AM PDT by Just another Joe
[ Post Reply | Private Reply | To 51 | View Replies]


Navigation: use the links below to view more comments.
first previous 1-2021-4041-6061-80 ... 361-378 next last

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
News/Activism
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson