Post #173,897
9/13/04 10:48:25 AM
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Where the hell is everybody?
I've got to stop reading modern sci-fi - it's depressing and bringing me down bigtime. I recently read [link|http://www.amazon.com/exec/obidos/tg/detail/-/0441009425/103-2882787-7520640?v=glance|Revelation Space] and I'm about 2/3 of the way through [link|http://www.amazon.com/exec/obidos/tg/detail/-/0345430778/103-2882787-7520640?v=glance|Manifold Space], both of which ask a very simple question:
Where the hell is everybody else?
(This isn't a book review, so I won't give their answer.)
If the conditions for life in the universe are commonplace, and even one species has survived past the madness that seems to possess us today to colonize the stars, we should see evidence everywhere of that activity. The heavy elements needed for the generation of life were created in the first wave of stellar activity in hypernovas, which means that second wave solar system formation would carry the necessary elements for life. The earth is OLD for a "second wave" planet, meaning that there have been plenty of opportunities leading up to now for others to take to the stars. Even at sublight speed, only several hundred million years would be needed to spread out and around the milky way galaxy, about as long as there has been vertebrate life on the surface of the earth.
So where are they?
"Raptured" out in a Vingean singularity?
Trapped by Brin's Crystal Spheres?
Destroyed by Berserker-class machines that are even now winging their way through the Oort cloud?
Or are we just blind to how communication works out there?
What's your take?
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Post #173,902
9/13/04 10:56:43 AM
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Easy...
They're all at the party the invitation list for which rude, uncouth primates are consistently passed over. I hear the entertainment is sublime. Can't have a bunch of hairless apes piddling on the crepes, after all.
I've read those books too; both have an interesting approach to answering the Question.
I guess at this stage of our development we might be better off alone than enslaved, or worse, encouraged to go enslave someone else.
Regards,
-scott anderson
"Welcome to Rivendell, Mr. Anderson..."
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Post #173,914
9/13/04 11:17:08 AM
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Light is slow. Universe is big. Catastrophes happen.
I haven't done the calculations recently, but I don't think it's surprising that we haven't found evidence of other civilizations yet.
On Earth, we've only had radio for ~ 100 years. We've only sent things out of our gravity well in the last 50 years. That's a tiny, tiny period of time in the greater scheme of things.
Consider what's happened on Earth in the last 2000 years (another blink of an eye):
Rome reached its peak and fell. Western civilization was in the doldrums for ~ 1000 years and only climbed back to where Rome was by ~ 1300 - 1400. We've had 2 horrific wars, and come close to destruction of civilization a couple of times.
It's a very slow process for civilization to advance. Destruction is far too easy to guarantee long-term monotonic increases in the capabilities of a civilization. And that says nothing about events out of any civilization's control (disease, planetary impacts of various kinds, giant methane releases, etc., etc.).
There probably are or have been other civilizations out there (I refuse to believe that we're unique), but they're so very far away that we may never find evidence for their existance.
Then there's the issue of the economics of it: Why would an advanced civilization spend the huge amounts of resources it would take to spread out (and find that needle in a haystack that has life) and make itself known? It's certainly very hard to justify here on Earth.
My $0.02.
Cheers,
Scott.
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Post #173,919
9/13/04 11:32:41 AM
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Not if you believe Von Neumann
As he demonstrated decades ago, the automated colonization of a galaxy is doable in a few million years, at a profit. That is, if you're capable as a species of planning on a horizon of a few centuries.
Capital markets have proven capable of pricing certain securities that do not pay back for a century. So we may prove capable of it. If that fails, and we last, some generation we just may have the hubris to do it anyways. Eventually sending machines to the next star will get cheap enough for a single wealthy individual to finance it.
Cheers,
Ben
To deny the indirect purchaser, who in this case is the ultimate purchaser, the right to seek relief from unlawful conduct, would essentially remove the word consumer from the Consumer Protection Act
- [link|http://www.techworld.com/opsys/news/index.cfm?NewsID=1246&Page=1&pagePos=20|Nebraska Supreme Court]
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Post #173,922
9/13/04 11:44:18 AM
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Looking for radio signals is probably futile.
Our own broadcast radiation has begun to decline as more efficient technologies are adopted. You really only need broadcast until your infrastructure is built out - which may take well under 200 years, so our planet may soon fall silent as well.
Further, there are modulation techniques which we've started using here where the signal can't be told from noise unless you are tuned to the proper reference signal, which may also look like noise and be undetectable unless you know where it is.
Deliberately sending clear contact signals makes no sense (aside from the expense). Suppose they attract a more technically advanced species with faster than light travel but highly paranoid and bent on destruction of any intelligence other than their own? It's the height of stupidity to project human (or Earth) logic on any unknown interstellar intelligence.
[link|http://www.aaxnet.com|AAx]
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Post #173,984
9/13/04 4:55:19 PM
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Re: Where the hell is everybody?
Some lamers have gone so far to adduce this as a method for deciding which vacuum string theory chooses from the gatrillions of choices. Needless to say it's "not science".
Someone even ventured the idea that the aliens aren't here because they've found a "better plane" and moved there.
-drl
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Post #173,986
9/13/04 4:57:57 PM
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So what's your answer?
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Post #173,989
9/13/04 5:01:01 PM
9/13/04 5:04:22 PM
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Don't think it's a valid question at this point
We still can't calculate the magnetic moment of the electron without illegal tricks. We aren't really very much off square one here.
The Universe is extremely big. You just can't fathom how big. Voyager will take 70,000 years to get to the nearest star.
The best answer I've seen is by Authur Clarke. "The stars are not for man." But, perhaps they are for what comes after man.
-drl
Edited by deSitter
Sept. 13, 2004, 05:04:22 PM EDT
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Post #173,993
9/13/04 5:16:22 PM
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Where? Well.. the Why has been done by Calvin & Hobbes
[yellowed copy on fridge]
Sometimes I think the surest sign that intelligent life exists elsewhere in the universe, is that none of it has tried to contact us.
Never mind that it is also cute; would you teach your autistic Billy-like child about ____ (anything potentially damaging to actually sentient life forms, if one is Power-drunk)
(Maybe they're waiting til we grow out of an affinity for Corporate Religions with Nasty Guys who enjoy crushing Universes - if a member doesn't genuflect properly.)
Now as to 'Where' - it's all inside, 'where'-less within the jelloware. Nothing exists which isn't a concept: we are blind to concept-free Space. Supposing we're just a test prototype; what not-to-do in the beta?
Red Herring, methinks.
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Post #174,077
9/14/04 12:29:44 AM
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The speed of light is too low.
Niven and Pournelle built a futuristic space-faring civilisation in The Mote In God's Eye that still managed to find an intelligent race no-one had ever seen before practically within sight of the Empire's seat. Basically, what had happened is that, due to the way their FTL drive worked, humankind had really only colonised a multitude of tiny islands in space. There were still vast, unexplorable seas between all of these they had never been in.
The speed of light currently makes it Very Hard to visit anything like a noticeable percentage of the universe, let alone a significant or even a decent percentage. Unless there is a loophole in physics enabling faster than light travel, this will remain so. Statistically, we just can't encounter any ETs.
Wade.
Is it enough to love
Is it enough to breathe
Somebody rip my heart out
And leave me here to bleed
| |
Is it enough to die
Somebody save my life
I'd rather be Anything but Ordinary
Please
| -- "Anything but Ordinary" by Avril Lavigne. |
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Post #174,079
9/14/04 12:35:34 AM
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It is clear the speed of light must be exceeded.
If it cannot be done by physics, then it must be done by metaphysics.
[link|http://www.aaxnet.com|AAx]
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Post #174,105
9/14/04 2:03:27 AM
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Not a joke!
-drl
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Post #174,175
9/14/04 11:05:12 AM
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I believe and nearly always have...
the Speed of Sound Barrier and the Speed of Light Barrier are things that need to be "Broken" in order to get to the next stage of travel. In effect a Technology Based Barrier. Breaking the Speed of Sound was doable only because of the magnitude was rather managable when the technology and the will were both sufficient. Much along the line of Quantum Technology being discoverd and researched today. I believe these are also link unexplicably. Sort of like Entangled Atoms. Entangled atoms affecting each other miles apart nearly (to me at least) proves that FTL travel *is* possible. Thereby the first 0.001" of the 10^6 Mile tall Iceberg has been exposed, giving an idea of the probable magnitude of the problem presented. The best part of this whole line of thinking: People used to think going faster than 100 MPH would kill you, period. It was believed that you would be crushed to death by the force of the Earth's gravity. HAH! -- [link|mailto:greg@gregfolkert.net|greg], [link|http://www.iwethey.org/ed_curry|REMEMBER ED CURRY!] @ iwetheyNo matter how much Microsoft supporters whine about how Linux and other operating systems have just as many bugs as their operating systems do, the bottom line is that the serious, gut-wrenching problems happen on Windows, not on Linux, not on Mac OS. -- [link|http://www.eweek.com/article2/0,1759,1622086,00.asp|source]Here is an example: [link|http://www.greymagic.com/security/advisories/gm001-ie/|Executing arbitrary commands without Active Scripting or ActiveX when using Windows]
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Post #174,176
9/14/04 11:16:36 AM
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The problem with C is that it's a hard limit.
Peter
[link|http://www.debian.org|Shill For Hire]
[link|http://www.kuro5hin.org|There is no K5 Cabal]
[link|http://guildenstern.dyndns.org|Blog]
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Post #174,178
9/14/04 11:21:51 AM
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I don't think we'll ever exceed C myself.
The difference between C and sound are quite a bit - C is literally the fastest any object can travel, whereas sound was just an engineering limitation.
Now, whether or not we can find shortcuts AROUND C, that's another thing entirely.
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Post #174,370
9/15/04 12:03:00 AM
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OT: What's C++ all about, then? :)
Two out of three people wonder where the other one is.
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Post #174,376
9/15/04 12:21:01 AM
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:-)
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Post #174,409
9/15/04 10:44:48 AM
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Demonstrating that you can't
Just when you thought you'd gotten to C, C's still larger. :-P
Cheers,
Ben
About the use of language: it is impossible to sharpen a pencil with a blunt axe. It is equally vain to try to do it with ten blunt axes instead. -- Edsgar W. Dijkstra
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Post #174,413
9/15/04 10:48:58 AM
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Hmmm
(C++) objects can't move faster than C?
Imric's Tips for Living
- Paranoia Is a Survival Trait
- Pessimists are never disappointed - but sometimes, if they are very lucky, they can be pleasantly surprised...
- Even though everyone is out to get you, it doesn't matter unless you let them win.
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Nothing is as simple as it seems in the beginning,
As hopeless as it seems in the middle,
Or as finished as it seems in the end.
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Post #174,414
9/15/04 10:58:15 AM
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Simple
That's the infinite mass expansion you get...
Regards,
-scott anderson
"Welcome to Rivendell, Mr. Anderson..."
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Post #174,179
9/14/04 11:22:50 AM
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Re: I believe and nearly always have...
They are fundamentally different "barriers". Sound barrier is just a misnomer for the development of a shock front (Mach cone) by an object going faster than sound. Light "barrier" is an intrinsic property of spacetime. In fact the essence of relativity is that there *is* no "light shock front" in vacuo. (There is a phenomenon called Cerenkov radiation that can be qualitatively understood as a light shock front in a material medium in which the effective SOL is less than C.)
[link|http://dept.physics.upenn.edu/balloon/cerenkov_radiation.html|http://dept.physics....ov_radiation.html]
In vacuo, a Mach cone for light is in principle impossible. Can't overstate this - nothing in our physical world will ever go faster than C. These facts are not open to any doubt, and are constantly verified in particle accelerators and cosmic ray studies.
-drl
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Post #174,181
9/14/04 11:27:36 AM
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There is no evidence that they affect each other
The Everett Interpretation explains all of the known phenomena of QM without concluding that there is any non-local "instantaneous interaction" going on with quantum entanglement.
Since the differences between interpretations are (as far as we know) fundamentally untestable, no other interpretation can manage to realize any usable information transfer at speeds above C.
Cheers,
Ben
To deny the indirect purchaser, who in this case is the ultimate purchaser, the right to seek relief from unlawful conduct, would essentially remove the word consumer from the Consumer Protection Act
- [link|http://www.techworld.com/opsys/news/index.cfm?NewsID=1246&Page=1&pagePos=20|Nebraska Supreme Court]
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Post #174,196
9/14/04 12:04:18 PM
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Replying to my own... to address the others.
Peter said: The problem with C is that it's a hard limit.
I didn't intimate that I didn't understand this. I just meant to say it is a technology barrier more than anything. C maybe Hard Coded. But that doesn't mean M isn't which infact it isn't. Making M "non-existant" would nake thing easier to do.
Thane said: The difference between C and sound are quite a bit - C is literally the fastest any object can travel, whereas sound was just an engineering limitation.
Now, whether or not we can find shortcuts AROUND C, that's another thing entirely.
Exactly. C sound are/were technology based barriers. Really the only thing we are missing is the technology... and just ignoring C as a limit is what will prolly happen. Or some type of shortcut as you point out.
Ross said: They are fundamentally different "barriers". Sound barrier is just a misnomer for the development of a shock front (Mach cone) by an object going faster than sound. Light "barrier" is an intrinsic property of spacetime. In fact the essence of relativity is that there *is* no "light shock front" in vacuo. (There is a phenomenon called Cerenkov radiation that can be qualitatively understood as a light shock front in a material medium in which the effective SOL is less than C.)
You missed my point about them being technology based. The issue at hand was something that was able to be handled mainly because the technology was there at the right place, and the Will to do it (or Hubris as others have said) was there in specific quantity. And in all reality, there could be a shock-wave front for light just as there was for the Sound barrier.
Ross continued: In vacuo, a Mach cone for light is in principle impossible. Can't overstate this - nothing in our physical world will ever go faster than C. These facts are not open to any doubt, and are constantly verified in particle accelerators and cosmic ray studies.
Thinking, without the "physical bounds", could you surmise, that quantum mechanics maybe different than either you or I understand it? What about finding that things smaller than atoms (the stuff atoms are bound from) actually have no mass. Whereas being able to excite them... maybe perhaps we become "ethereal or non-massive"... I want you to understand, throwning theory at this discussion will do nothing but make it flounder. I am talking about technology, that right now, humans as a race, have neither the ability nor the understanding needed to do this. Either some type of Enlightenmnet is needed, or research producing this knowledge is needed.
Ben said: The Everett Interpretation explains all of the known phenomena of QM without concluding that there is any non-local "instantaneous interaction" going on with quantum entanglement.
Since the differences between interpretations are (as far as we know) fundamentally untestable, no other interpretation can manage to realize any usable information transfer at speeds above C.
Yes, I understand this point. Well taken. No other interpretation can manage to realize any usable information transfer at speeds above C, *YET*. Maybe never.
-- [link|mailto:greg@gregfolkert.net|greg], [link|http://www.iwethey.org/ed_curry|REMEMBER ED CURRY!] @ iwetheyNo matter how much Microsoft supporters whine about how Linux and other operating systems have just as many bugs as their operating systems do, the bottom line is that the serious, gut-wrenching problems happen on Windows, not on Linux, not on Mac OS. -- [link|http://www.eweek.com/article2/0,1759,1622086,00.asp|source]Here is an example: [link|http://www.greymagic.com/security/advisories/gm001-ie/|Executing arbitrary commands without Active Scripting or ActiveX when using Windows]
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Post #174,183
9/14/04 11:30:04 AM
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Metaphysics wise
Perhaps the question is not whether we can successfully exceed the speed of light. The real question is whether we can make light go faster?
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Post #174,195
9/14/04 12:03:09 PM
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Re: Metaphysics wise
The problem is, the term "speed of light" is a misnomer. It's a parameter characteristic of the world (like Planck's constant) that happens to have the dimensions of a velocity. It's not really the speed of anything - light happens to go at that speed because it is massless. Any other massless thing will also go at that speed. And anything that goes at C, only goes at C - that is, can never be brought to rest.
Likewise, Planck's (reduced) constant has the dimensions of angular momentum, while not in itself being the angular momentum of anything in particular. It turns out that a measurement of angular momentum will always produce an integral multiple of 1/2 hbar.
-drl
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Post #174,198
9/14/04 12:08:02 PM
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No...
It turns out that a measurement of angular momentum will always produce an integral multiple of 1/2 hbar.
Perhaps it should do that, but I have great confidence in the ability of your average student in a physics lab to actually get any (im)possible value when they actually try to do that measurement.
Cheers,
Ben
To deny the indirect purchaser, who in this case is the ultimate purchaser, the right to seek relief from unlawful conduct, would essentially remove the word consumer from the Consumer Protection Act
- [link|http://www.techworld.com/opsys/news/index.cfm?NewsID=1246&Page=1&pagePos=20|Nebraska Supreme Court]
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Post #174,207
9/14/04 12:55:53 PM
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Re: No...
I had a friend who measured the refractive index of something and came up with 6! :)
Of course I meant "measurement" in the sense of the measurement problem, the "other half of quantum mechanics" that gives the formalism physical meaning.
And of course you can accurately measure the angular momentum of, say, [link|http://www.if.ufrgs.br/~betz/quantum/SGtext.htm|silver atoms].
-drl
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Post #174,212
9/14/04 1:32:33 PM
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There are materials with negative refractive indexes.
Lots of weird things are being discovered these days.
[link|http://physicsweb.org/articles/world/16/5/3/1|Physics Web].
I think c will stand as a limit for a while though. :-)
Cheers,
Scott.
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Post #174,217
9/14/04 1:53:55 PM
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Re: There are materials with negative refractive indexes.
Neat, I'll have to look at that some more.
Just to close this issue - C is *not* a barrier or a limit or even the speed of anything in particular. It's a parameter that characterizes the actual world.
Note that Euclidean geometry has exactly such a parameter - but it is imaginary! That is, in relativistic geometry we can think of the equation
x^2 - (ct)^2 = 0
and factor this to
(x-ct)(x+ct) = 0
so either x/t = c or x/t = -c. The parameter then represents the relative scale of the space to the time axis.
Now, it turns out that metric geometry (with a Pythagorean-like theorem) is a special case of projective geometry, and that the special type of metric geometry (Euclidean or pseudo-Euclidean = relativistic) is determined by the equation for a "degenerate conic", which is one that looks like
x^2 + y^2 + ... = 0
Euclidean plane geometry is then characterized by the equation
x^2 + y^2 = 0
which can be factored into
(x+iy)(x-iy) = 0
The characteristic parameter of Euclidean geometry is i, the imaginary unit! The points x and y satisfying this equation are called the "circular points at infinity". So, in a sense, Euclidean geometry has a thing called "infinity" that is such that you can never get closer to it. This is exactly analogous to the parameter c in relativity, which has a speed that can never be attained. Thus
relativity = the light cone
Euclidean geometry = the points at infinity
-drl
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Post #174,199
9/14/04 12:08:53 PM
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Well, if we can't speed up light....
...can we at least try to slow it down? :-)
(Methinks a cup of hot tea is needed to bring about the Improbability Drive.)
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Post #174,328
9/14/04 9:12:32 PM
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That would be one of my favourite passages. :-)
Is it enough to love
Is it enough to breathe
Somebody rip my heart out
And leave me here to bleed
| |
Is it enough to die
Somebody save my life
I'd rather be Anything but Ordinary
Please
| -- "Anything but Ordinary" by Avril Lavigne. |
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Post #174,080
9/14/04 12:37:14 AM
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It's not the getting there, it's slowing down enough to look
I can drive across the U.S. in four days. Three if I don't sleep and get really lucky. Doesn't mean I'll know what the hell was in any of it.
===
Implicitly condoning stupidity since 2001.
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Post #174,107
9/14/04 2:11:13 AM
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Right
We can get anywhere we want as long as we can go fast enough, and time dilation makes it possible to, say, get to Andromeda and back in a few thousand years (and of course back on Earth 4 million years have passed). During most of the trip, due to aberration, the Universe will appear to be an X-ray dot in the direction of motion. How to navigate? It's like driving across the country looking through a pinhole covered by a welder's glass.
-drl
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Post #174,104
9/14/04 2:01:32 AM
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Re: The speed of light is too low.
Things like the binding energy of the electron to the hydrogen nucleus depend on C. Change C and everything changes.
You can easily imagine a world where C is very low - just speed yourself up tremendously. You end up in a world that is essentially frozen - the days are millenia long, it takes eons for anything to happen, gravity is very weak (nothing to hold you down). C represents the "stiffness" of space with respect to time - a low C means a very, very stiff world. The fact the C is large allows for a fluid existence relative to our psychological time scale. For C->infinity, gravity is impossible, and the world as we know it is impossible.
There is no free lunch. It's a trade-off - either the outer world is impossibly large or the local world is impossibly dull.
-drl
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Post #174,082
9/14/04 12:40:45 AM
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Space is big.
Very, very big.
Peter
[link|http://www.debian.org|Shill For Hire]
[link|http://www.kuro5hin.org|There is no K5 Cabal]
[link|http://guildenstern.dyndns.org|Blog]
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Post #174,083
9/14/04 12:49:29 AM
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I believe the technical term for it is ... hyarge
===
Implicitly condoning stupidity since 2001.
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Post #174,115
9/14/04 2:27:15 AM
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Not so big
If it encounters a phenomena capable of prolonged exponential growth. Particularly over geological timescales.
Which was Von Neumann's point. Once a civilization starts expanding, its ability to expand also expands. The result is an exponential ability to consume local resources, which is more than enough to fuel an indefinite spread through the galaxy at rates which are only limited by Einstein's theories. The result at 1% of the speed of light is 10 million years to cover the galaxy - which is an eyeblink in geological time. Even at 0.1% of the speed of light we could easily reach and colonize the entire Local Cluster (that includes the Andromeda galaxy) before the Sun burns out.
It take a truly astronomical coincidence (no pun intended) to find another advanced technological society in our galaxy that has not yet arrived at Earth.
Cheers,
Ben
To deny the indirect purchaser, who in this case is the ultimate purchaser, the right to seek relief from unlawful conduct, would essentially remove the word consumer from the Consumer Protection Act
- [link|http://www.techworld.com/opsys/news/index.cfm?NewsID=1246&Page=1&pagePos=20|Nebraska Supreme Court]
|
Post #174,185
9/14/04 11:41:48 AM
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Question about that theory
Does he say that we could have reached any place in that area, or that we could have colonized all places in that area?
===
Implicitly condoning stupidity since 2001.
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Post #174,194
9/14/04 12:02:22 PM
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The latter
We can get exponential growth if we have unlimited resources but are limited to cubic growth by Einstein.
Since exponential growth is faster than cubic, in the limit we can theoretically completely use the resources of an expanding volume of space.
Cheers,
Ben
To deny the indirect purchaser, who in this case is the ultimate purchaser, the right to seek relief from unlawful conduct, would essentially remove the word consumer from the Consumer Protection Act
- [link|http://www.techworld.com/opsys/news/index.cfm?NewsID=1246&Page=1&pagePos=20|Nebraska Supreme Court]
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Post #174,124
9/14/04 3:28:52 AM
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I thought it was a long way to the chemists. But that's
just peanuts to space.
And so on.
Two out of three people wonder where the other one is.
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Post #174,089
9/14/04 1:21:13 AM
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Don't know enough
Humans don't really know enough to create a meaningful guess, let along an answer.
But that doesn't stop us from producing wild speculation. My personal guess is that sentient life is very rare.
When people conjecture that sentient life is common, they are generally assuming that life is common and once life occures sentient life is almost inevitable.
Biology however suggests that the second part is not valid. There is good reason to believe that a lot of worlds will never advance beyond single celled life. And even if it gets past that point their is no reason to think that sentient life forms are even a likely result.
Jay
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Post #174,106
9/14/04 2:04:39 AM
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Re: Don't know enough
I dunno - a significant percentage of the natural chemical elements (6 of 92) are needed for life, so a lot of the world is "lively". I'm certain that life is common, but sentient life? One can only speculate until another example is at hand. My gut feeling is - very common.
-drl
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Post #174,126
9/14/04 3:30:59 AM
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Might like some MMORPGs
Players on one world can't see another - requires too much bandwidth and the lag is sucky.
Two out of three people wonder where the other one is.
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Post #174,169
9/14/04 10:52:02 AM
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Your .sig is oddly appropriate. :)
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