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Haglund
2003-Nov-01, 02:20 PM
The theoretical physicist Dr. Michio Kaku has an interesting article about "The Physics of Extra-Terrestrial Civilizations - How advanced could they possibly be?"

http://www.mkaku.org/articles/physics_of_a...lien_civs.shtml (http://www.mkaku.org/articles/physics_of_alien_civs.shtml)

Fraser
2003-Nov-01, 04:22 PM
Cool, that was a great article.

Tinaa
2003-Nov-01, 04:56 PM
I agree, that was fun to read. The book Ringworld and Star Trek books and shows have visited this idea, among others. What would it be like to harness the power of the sun? Even the amount that hits our small little world.

kashi
2003-Nov-02, 01:33 AM
Great article, except for the bit about rock music and Hollywood films being global culture. India makes much more films than America, but we don't call Bollywood films global culture.

kashi
2003-Nov-02, 01:37 AM
Another thought. If the universe is to end in a big chill...won't the enormous energy consumption of a type III civilisation speed up this process?

If you ask me, a wise, advanced civilisation would opt against high energy usage.

Tinaa
2003-Nov-02, 05:45 PM
I sure hope what Hollywood puts out is not considered global culture.

Isn't entrophy the way of the universe? Using the energy wouldn't make it go away any faster. Maybe the harnessers of galactic energy may find a way to recycle the energy!

Planetwatcher
2003-Nov-02, 09:17 PM
Interesting indeed. ;)
You might know that a Dyson Sphere is between the lines in at least one scerero of a type II civilisation . ;)

However, I find that somewhat counterdictory, because to build a Dyson sphere would require more material then everything in our solar system minus the sun itself. To obtain such an endeavor would require the techical abilities of a type 3 civilisation. For whom a Dyson sphere would not be nearly enough energy. :unsure:

And furthermore, to move from fossel fuels to something more advanced for energy, what would the Republicans have to say about all that. :lol:

Tinaa
2003-Nov-02, 09:24 PM
Planetwatcher, as Republican I say GREAT! :D No more fossil fuels and free energy. Just think of the ground vehicles of the future. Make a Humvee look like a VW bug!

Haglund
2003-Nov-02, 09:51 PM
Originally posted by kashi@Nov 2 2003, 01:33 AM
Great article, except for the bit about rock music and Hollywood films being global culture. India makes much more films than America, but we don't call Bollywood films global culture.

Yeah but are they as popular on a global level as the Hollywood stuff is?




Another thought. If the universe is to end in a big chill...won't the enormous energy consumption of a type III civilisation speed up this process?

If you ask me, a wise, advanced civilisation would opt against high energy usage.

Yes, but it depends on what you want to do, how much energy do you need for that, etc.? For example, only to send a moderately sized interstellar ship to another star will require enormous amounts of energy. Also, our population grows, and we want to colonize the solar system and other star systems, maybe do terraforming, etc. And besides, wouldn't it be better to use the energy that there is in the universe rather than having it radiating out everywhere? And besides, a really advanced civilization might have the capacity to reconstruct certain parts f the universe or that entire universe, to keep it from dying a Big Chill death. And to do that would require them to use up large parts of the universe itself I guess :)

QJones
2003-Nov-02, 10:48 PM
Hmmn, an advanced civilisation could actually slow the death of the universe. If they could 'throttle' the sun, to burn (edit) slowler and cooler, the sun would actually last quite a bit longer. The solution to 'cooler sun' would be to move the Earth closer.

Actually, if a civilisation could somehow utilise 100% of a stars energy, then it would make more sense to 'shut down' the sun and utilize the fuel according to their desires.

For example, using the wonders of fusion, you could set up a completely viable civilisation around a gas giant. You wouldn't even need the Sun, since controlled-fusion would give you all the heat required. And since the gas giant isn't 'wastefully' burning to cause 'light', it would last longer.

QJones
2003-Nov-02, 10:51 PM
Hey, if only 1/2 of the baryonic mass is accounted for by stars, couldn't the other 1/2 be accounted for by 'cold' stars. i.e., ones that weren't lit. There could be aliens there that we'd never see.

baryonic = Consisting of baryons - protons and neutrons - baryonic matter is "normal" matter. The Sun and the Earth are made of baryonic matter.

Matthew
2003-Nov-04, 06:27 AM
What about a type 4 civilisation? One which could effectivley prevent the universe from expanding or collapsing, by manipulating gravity itself. A type 4 civilisation may be able to cross into different universes as well.

kashi
2003-Nov-04, 07:04 AM
This is all based on theory that is far from conclusive. I find the whole notion of classifying civilisations purely on their energy consumption quite ridiculous.

Planetwatcher
2003-Nov-04, 07:24 AM
Tinaa, you are among the few Republicans in Texas who favors energy sources other then oil. But then you are likely better educated too.

I seem to remember an old Star Trek episode in which the population lived inside a planetoid traveling through space to a new star. Then Next Generation also used that as a plot. I'm wondering if that would qualify as a type 2.

Matthew
2003-Nov-04, 08:23 AM
This is all based on theory that is far from conclusive. I find the whole notion of classifying civilisations purely on their energy consumption quite ridiculous.

You have to base them on something. Maybe technological advances.

Haglund
2003-Nov-04, 05:47 PM
Originally posted by kashi@Nov 4 2003, 07:04 AM
This is all based on theory that is far from conclusive. I find the whole notion of classifying civilisations purely on their energy consumption quite ridiculous.
Just one way of classifying them, but I find it to be a pretty good way. After all, your activities decide on how much energy you need. For example a culture with a really low tech doesn't need much other than heating up their homes. We need more in order to heat our homes and water, and to produce and use all electric equipment, to make the cars roll and the aeroplanes fly, to make all the industries and factories go, even lift payloads into orbit and beyond. We will need much more to colonize other planets and to terraform them. I think that you won't produce much more energy than you need. Of course we can imagine a civilization with a really high population, using up a lot of energy because of this even though their technological level is low. But still, someone who wants to reengineer entire planets and restructure a solar system will need much much more anyway... But yes, this is just a system to classify them one way, there must be others as well.

Polarbeast
2003-Nov-04, 09:11 PM
This is all based on theory that is far from conclusive.

Exactly so... which Dr. Kaku noted at the beginning and the end of his essay.


I find the whole notion of classifying civilisations purely on their energy consumption quite ridiculous.

Not so much on energy consumption... but on their ability to harness energy. Certain technological ability requires immense amounts of power, which is why we can't figure out how to travel through interstellar space properly or stop losing socks in the wash.

I imagine that an advanced civilization would naturally use less "energy" than we in small, unimportant ways (emission of wastes, fossil fuels, etc.), and that they would be interested in using less energy to perform something than expected. But, as Parker pointed out, a civilization as it progresses is increasingly able to make use of larger amounts of energy. Rocks -> fire -> electricity -> nuclear power -> and so on.

Polarbeast

kashi
2003-Nov-05, 05:13 AM
I would like to think that after advancing a great deal, in the future we will need less energy per person as our usage will be more efficient.

QJones
2003-Nov-05, 08:07 AM
Kinda. I think some of our consumptions will go down (for example, I now use one of those super-efficient 14 watt bulbs to read by) - but at the same time, our constructions will require more energy. It takes a lot more to make an aircraft carrier than a longship.

I think that limiting the system to how many 'suns' of energy is a little naive - that's already assuming that fusion and the Sun are near-ultimate sources of energy.

A neat variation would be solar equivalents. "Yep, my spaceship gets 8 light years to the solar*day". In other words, the amount of energy pumped out each day by a star.

Matthew
2003-Nov-05, 10:04 AM
A neat variation would be solar equivalents. "Yep, my spaceship gets 8 light years to the solar*day". In other words, the amount of energy pumped out each day by a star.

What do you mean?


How about grading advanced civilisation on how much they actually know. Not power consumption, thats a variable. Some advanced races may use a lot of energy, no care for how much they use for they have an almost unlimited amount, while Kashi has pointed out that some may try to conserve enrgy using their knowledge.

kashi
2003-Nov-05, 11:20 AM
Indeed. If we're talking about a wise civilisation (which would happen eventually once a civilisation is advanced technologically), maybe they'd opt to keep their citizens happy, leading simpler lives requiring less energy.

dnav
2003-Nov-05, 03:02 PM
An interesting article, that may more define our future (humanoids) than alien civilizations. I wonder if we can ever come to terms with aliens life possibilities so long as we confine ourselves to our understanding of how life, and the universe, exists. Physics, energy usage, relativity, etc, work well for our limited role in the overall scheme of things, but prevent us from looking very far "outside the box".

GOURDHEAD
2003-Nov-05, 03:36 PM
Note that the system and processes described in
Interstellar Transportation (http://hometown.aol.com/malcolmbmcneill/InterstellarTransportationExplo.html) and again at here. (http://home.comcast.net/~mbmcneill7/) offer a crude roadmap including a viable beginning for launching us on our way to type III and beyond civilizations. Once started, the very development of this system will generate accelerating rates of technology improvement by discovering problems and forging their solutions. Those who DO make mistakes and learn from them.

With all due respect to Carl Sagan's memory, our corner of the universe is no less significant than any other and I choose to believe that our potential for reaching the heights of technological development are no less than any other. Although we may not be the most advanced now. ;)

Haglund
2003-Nov-05, 03:42 PM
Originally posted by matthew@Nov 5 2003, 10:04 AM
How about grading advanced civilisation on how much they actually know. Not power consumption, thats a variable. Some advanced races may use a lot of energy, no care for how much they use for they have an almost unlimited amount, while Kashi has pointed out that some may try to conserve enrgy using their knowledge.

A great way to classify civilizations, but at the same time, there will be a limit when you can't develop much more unless you increase your energyconsumption. Also, to gain more knowledge requires more energy too. Maybe we could develop some sort of scale using different kinds of factors to grade civilizations... should be interesting. Energy usage, low or high? Knowledge, technology... what more could we add to this, perhaps art? Things like that. Any ideas?

Matthew
2003-Nov-05, 07:44 PM
But they may not be an arty race.

I think they should be graded on:
Technology. An advanced civilisation will have more advanced technology.
Knowledge. A more advanced civilisation wwould have accumulated more knowledge, and would have discovered more.
Energy usage. An advanced civilisation would either not care about how much energy they use because they can access an almost unlimited supply of it. Or they decide to preserve energy and use as little of it as possible. Although this little amount that they might use would probably be much more than we use, or maybe not.

Haglund
2003-Nov-05, 10:23 PM
But the thing is, it's also about survival. You want to make sure your species will survive most if not all imaginable natural disasters. As the article says "By definition, an advanced civilization must grow faster than the frequency of life-threatening catastrophes." And this will require lots of energy, for example to avoid large meteorite impacts, or global iceages, or even to spread to other worlds to minimize the risks. Technology, knowledge and energy usage seem to go hand in hand.

kashi
2003-Nov-06, 09:14 PM
What about micro-organisms that can endure much more than humanoids? They're not advanced but they're probably going to last longer than we are!

QJones
2003-Nov-06, 11:55 PM
That's why energy consumption is a good standard. Germs are excellent survivors. Ants are excellent builders. However, neither of them will ever process more energy than what's available on a planet.

It is possible that a microbe could travel between the stars (their planet broken apart and thrown into interstellar space). If it survived and prospered, the microbes would still only be using the energy available to a planet.

jeanne v.
2003-Nov-12, 01:06 AM
great paper! how can anyone NOT wonder what other civilizations look like??!! let's just hope they aren't all "borgs"!

Matthew
2003-Nov-12, 08:21 AM
great paper! how can anyone NOT wonder what other civilizations look like??!! let's just hope they aren't all "borgs"!

In this topic we are not looking at what aliens look like.


But the thing is, it's also about survival. You want to make sure your species will survive most if not all imaginable natural disasters. As the article says "By definition, an advanced civilization must grow faster than the frequency of life-threatening catastrophes." And this will require lots of energy, for example to avoid large meteorite impacts, or global iceages, or even to spread to other worlds to minimize the risks. Technology, knowledge and energy usage seem to go hand in hand.

To prevent a life threating situation you do not necessarily require more energy than we currently have. Going to the Moon is feasable, currently. True the energy usage of launching a rocket is greater than any other know races energy usage, but it is not above and beyond what we currently can do, we already have. Destroying asteroids may require a few nuclear bombs, or a low energy prevention (eg. solar sail) But yes as a rule of thumb it would require more energy than we can currently, easily, cumulate to prevent a life threatening situation. But I think the less time we have to prevent a situation, the more energy we would need.

But remember there is also good luck, a civilisation may be born out of the ashes of a previous situation and have a huge amount of good luck and not have a serious disater for millions of years until they have more than enough rescources to prevent the catastrophes.

GOURDHEAD
2003-Nov-12, 03:49 PM
Here's an overview of ideas presented in my Interstellar Transportation proposal which uses current technology (including reasonable expectations for near term improvements) for the most part. By attempting to implement this system we can enhance our survival by reducing the natural hazards that can otherwise prevent us from achieving the advanced levels of civilization postulated for our cosmic neighbors. In order to survive and evolve, sets of living organisms must alter their local environment. The sentient ones will learn to do so beneficially. Extrapolating from "Cortez and the Aztecs" we would be wise to learn to deal with non-benevolent advanced sentients while achieving and practicing benevolence ourselves.

The lone termite beholds its maturing mound incapable of awe.
One built by the termite and its moundmates driven by biological law.
Pursuing an unconscious urge within their genes constructed;
Daring humans to do what human consciousness has instructed?
These termites persist by the grace of the aardvark's claw,
And humans thrive by that of the asteroids orbits' pitch and yaw.
Ever looking askance anticipating the supernova's power raw,
In anxious quandary about the skewed orbit of a black holes's maw
And not unmindful of patient earth's restless crust's upheaval;
Knowing each can place this single basket of humans beyond retrieval.
:rolleyes:


ABSTRACT
An operational concept for developing and implementing interstellar transportation and exploration as well as enhancing travel to and the colonization of the solar planets is described. The Alpha Centauri System can be reached within 10 (where 40 years is a piece of cake) years after trip initiation from the Solar System. Exploration of the entire Milky Way galaxy is achievable as the system expands from star to star. Vehicle velocity profiles with greater than 0.5 light speed have been tabulated including the power levels required. The method of acquiring this power is outlined. The design uses propellant exhaust rates on the order of a few hundred kilograms (rest mass) per second, expelled at relativistic velocities, and photon sail effects. The assumption is made that this much mass is available in interplanetary and interstellar space or can be made available via soloton-like particle beams radiated from the trip initiating star. High level system requirements and design approaches are included.

OPERATIONAL CONCEPT
This operational concept is for interstellar transportation, solar and extrasolar planet colonization, and the exploration of distant stellar systems. It requires a system comprising 4 independent interfacing major elements as presented in the system description. This concept defines the starting point that is expected to require benefit of the knowledge gained from its evaluation and implementation.

CONSTRAINTS
Propellant exhaust velocities (Ve) must be an appreciable fraction (0.3 to 0.5) of the speed of light to minimize the total propellant mass.

The propellant exhaust velocities produced by chemical combustion processes are orders of magnitude smaller than 0.3c therefore, chemical combustion processes are ruled out of consideration for interstellar distances.

Fission processes at the required energy levels are too mass intensive.

Fusion processes for the required energy levels are currently out of reach
and are likely to remain so for 250 or more years.

Matter/antimatter propulsion processes capable of providing energy at the
required levels will defy our cleverness for yet another two or more centuries.

Zero point vacuum energy harnessing and wormhole exploitation processes
are too heavily invested in imagination to merit serious consideration.

The nearly perfectly collimated beamed energy must be sufficient to provide 10^17 to 10^19 watts and the receiving surface must be as small as it can be and acommodate power densities on the order of .01 to 10 megawatts per square meter. The design goal is to limit the mass of the receiving surface including its support structure to no more than than 99% of the total mass of the vehicle.

D. Sole sail is a soul sale. Plasma rocket propulsion is required to achieve the desired orbit at the destination stellar system.

ASSUMPTIONS
A. Photovoltaic efficiencies of 50% or greater will be available within 20 years.

B. Material and or processes can be selected (or developed) to accommodate the
mass to thrust ratios and power density characteristics required by the
system descriptions.

C. The system can be extended from each stellar system to the next by either
transporting the essential components from “the next star back”
or manufacturing them in place where suitable natural platforms (planets
and/or their moons) are found or can be assembled.

D. Sufficient material exists in interplanetary and interstellar space to supply
the propellant mass required for propulsion. It is the nature of the
gravitational forces at play in each stellar system to cause cometary and
asteroidal objects and materials to be expelled into galactic orbits thus
providing both propellants and hazards. What we think of as the Oort cloud
may turn out to be, or more likely, merge with "a continuum" of material in
galactic orbit among the stars.


The earth is but humanity's cocoon precariously attached to the solar system which is but a twig on the galactic tree. Now is the time for the imago to emerge and explore the tree----and eventually, its neighbors. Shall our dreaming limit our vision of progress to having our descendants do less than engineer the expansion of the universe...with appropriate deference to the will and grace of God of course?

;)

Matthew
2003-Nov-13, 09:05 AM
Good piece of work!

But some of the things you outlined we might not discover how to utilise for 30 or more years, is that still classed as in the near forseeable future? I do not know.

But we may discover things like false vacuum, tomorrow, all it takes is for someone to come up with a really, really clever idea and develop it. Like Einstein did. Its unlikely though...

daddy
2004-Apr-16, 03:20 AM
isn't it weird that we try to prejudge another civilization that doesn't exist by our expectations that change every day.

GOURDHEAD
2004-Apr-16, 02:02 PM
isn't it weird that we try to prejudge another civilization that doesn't exist by our expectations that change every day.

It's not only not wierd, it's the only way open to us. Extrapolation from where we are and what we know, and what we can easily imagine, are our only tools and quite valuable. It puts us in a better position than are slugs and earthworms and maybe even most other primates.

kashi
2004-Apr-16, 03:01 PM
Lol. Daddy has a point though. Given the diversity of civilisations on Earth, perhaps we shouldn't be so quick to make prejudgements.

GOURDHEAD
2004-May-08, 02:18 AM
Daddy has a point though. Given the diversity of civilisations on Earth, perhaps we shouldn't be so quick to make prejudgements.

Au contrare! We have been and are being much too slow. Our very survival depends on our exploring the likely outcomes of contacts with extraterrestrials. Carbon based critters are very likely simply because of the nature of carbon. Intelligence and aggression go together because the more intelligent anticipate dangers, alas sometimes falsely, and attempt to posture themselves to avoid their own destruction leading to the conclusion that the best defense is the best offense you can employ. From the most general of perspectives the civilizations of the Inca and the Aztecs, except for more primitive technology and barbaric religious practices, were not that different from that of the European states.

Clipper
2004-May-08, 02:53 AM
A truly fascinating article.