[go: nahoru, domu]

Jump to content

Kardashev scale

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by 66.227.203.49 (talk) at 10:19, 8 January 2007 (→‎See also). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Kardashev scale projections ranging from 1900 to 2100.

The Kardashev scale is a general method of classifying how technologically advanced a civilization is, first proposed in 1964 by the Russian astronomer Nikolai Kardashev. It has three categories, based on the amount of usable energy a civilization has at its disposal and increasing logarithmically:

  • Type I — A civilization that is able to harness all of the power available on a single planet, approximately 1016 W. The actual figure is quite variable; Earth specifically has an available power of 1.74×1017 W. Kardashev's original definition was 4×1012 W. (Kardashev had originally defined Type I as a "Technological level close to the level presently attained on earth", "presently" meaning 1964.)
  • Type II — A civilization that is able to harness all of the power available from a single star, approximately 1026 W. Again, this figure is variable; the Sun outputs approximately 3.86×1026 W. Kardashev's original definition was 4×1026 W.
  • Type III — A civilization that is able to harness all of the power available from a single galaxy, approximately 1036 W. This figure is extremely variable, since galaxies vary widely in size. Kardashev's original definition was 4×1037 W.

All such civilizations are purely hypothetical at this point. However, the Kardashev scale is of use to SETI researchers, science fiction authors, and futurists as a theoretical framework.

Usage and examples

Human civilization is currently somewhere far below Type I, as it is able to harness only a portion of the energy that is available on Earth. The current state of human civilization has thus been named Type 0. Although intermediate values were not discussed in Kardashev's original proposal, Carl Sagan argued that they could easily be defined by interpolating and extrapolating the values given above. He calculated humanity's current civilization to be 0.7. He used a power output of ~10TW and the formula:

where K is a civilization's Kardashev rating and W is its power output in watts. Note that Roman numerals must still be used for the integer part of a civilization's rating, while the fractional part is written in decimal.

A possible method by which Earth can advance to a Type I civilization is to begin the heavy use of ocean thermal energy conversion, wind turbines and tidal power to obtain the energy received by Earth's oceans from the Sun. However there is no known way to successfully utilize the full potential of Earth's energy production without complete coating of the surface with man made structures. In the near and medium future, this is an impossibility given humans' current lifestyle. We are, however, already "harnessing" Earth's production through our dependence upon ecosystem services, which may prove more efficient and sustainable than our own technology well into the future. If we choose never to fully substitute synthetics for nature's services on this planet, we may still achieve a Type I civilization by assuring that Earth's ecosystem services are maximally functional.

A hypothetical Type II civilization might employ a Dyson sphere or other similar construct in order to utilize all of the energy output by a star, or perhaps more exotic means such as feeding stellar mass into a black hole to generate usable energy. Alternatively, it may occupy a large number of solar systems, absorbing a small but significant fraction of the output of each individual star. A Type III civilization might use the same techniques employed by a Type II civilization, applied to all of the stars of one or more galaxies individually, or perhaps might use other mechanisms not yet proposed.

A common and recognisable example of a fictional civilization capable of entering a Type III level is the Galactic Empire which is featured in many works of space opera. These civilizations utilise energy on a massive scale, generally being in between Type II and Type III.

Possible timeline

Humanity's current history indicates a timeline roughly shown here. These values are approximate, and include future predictions, from 0.8 onwards. They use Sagan's extrapolated version of the scale.

Type 0 Development of Civilization
0.25 (3 108 W) Roman Civilization 0.5 (1011 W) Industrial Revolution 0.6 (1012 W) 1891 to 1938 technological expansion 0.7 (1013 W) c. 2000: Nuclear Weapons and Fission power 0.8 (1014 W) Fusion power[citation needed] 0.9 (1015 W) Space elevators, the creation of an Ecumenopolis[1] Type 0 to Type I transition
Trends:
Increasing levels of technology, Up to 0.5, increasing levels of fragmentation, increasing energy usage, increasing area of habitation[citation needed]
After 0.5, Decreasing levels of fragmentation[citation needed]

Function as a teleology

When transformed from a scale of energy use measurement into a predictive, or normative, description of desirable future technology the Kardashev scale becomes teleological: it predicts an "end of history". As a description of past and future human history it should be compared with the Marxist theory of modes of production which makes similar assertions about combinations of technological and social structures, albeit across a shorter time span.[citation needed]

Weakness by supposition?

Energy Consumption from 1989 to 1999

It has been argued that, because we cannot understand advanced civilizations, we cannot predict their behavior; thus, Kardashev's visualization may not reflect what will actually occur for an advanced civilization. This central argument is found within the book Evolving the Alien: The Science of Extraterrestrial Life.[2]

Civilization implications

There are many historical examples of civilizations undergoing large-scale transitions, such as the Industrial Revolution and the Renaissance. The transition between Kardashev scale levels could potentially represent similarly dramatic periods of social upheaval, since they entail surpassing the hard limits of the resources available in a civilization's existing territory. A common speculation[citation needed] suggests that the transition from Type 0 to Type I might carry a strong risk of self-destruction since there would no longer be room for further expansion on the civilization's home planet. See Malthusian catastrophe for an example of such a speculation.

Contact constraints

For pre-Type I civilizations, it is costly to attempt contact with other more advanced civilizations because of the energy output needed. It has been predicted that in order to provide a reliable contact beacon of sufficient power to be noticeable to a Type II civilization, it must output such high energy levels that the cost would be around $1 billion in energy.[3] As a result it has been suggested that civilization must advance into Type I before the energy required for reliable contact with other civilizations becomes sufficiently low that it does not drain a civilization's economic resources.

Once civilizations have discovered each others' locations, however, the energy requirements for maintaining contact and exchanging information can be significantly reduced through the use of highly directional transmission technologies. In 1974, the Arecibo Observatory transmitted a message toward the M13 globular cluster about 25,000 light-years away, for example, and the use of larger antennae or shorter wavelengths would allow transmissions of the same energy to be focused on even more remote targets. See SETI for extensive discussion of these possibilities.

Extensions to the original scale

Zoltan Galantai has defined a further extrapolation of the scale, a Type IV level at 1046W that is within a few orders of magnitude of the energy output of the visible Universe. Such a civilization approaches or surpasses the limits of speculation based on current scientific understanding, and may not be possible. Frank J. Tipler's Omega point would presumably occupy this level, as would the Biocosm hypothesis. Galantai has argued that such a civilization could not be detected, as its activities would be indistinguishable from the workings of nature (there being nothing to compare them to). [4]

However, Milan M. Ćirković has argued that "Type IV" should instead be used to refer to a civilization that has harnessed the power of its supercluster, or the "the largest gravitationally bound structure it originated in."[5] For the Local Supercluster, this would be approximately 1042 W.

Hypothetical futures

Science fiction, having extended these values has also provided guides for possible future changes associated with the fractionalized version of the Kardashev scale. One possible future is presented here. The majority of the assumptions presented here are derived from scientific literature. Nikolai Kardashev's article "On the Inevitability and the Possible Structures of Supercivilizations",[6] where he explains that with increasing energy levels come increasing technology, decreasing cohesiveness, and varying likelihood of survival and contact, largely is a guide to this section. These civilizations and the changes within them are also referenced in Kardashev's papers "Cosmology and Civilization"[7] and "Transmission of Information by Extraterrestrial Civilizations".[8] The last framework for these explanations can be found at Energy and Culture, chapter 15.[9] This article provides a much more detailed explanation than that which exists here. It presents a theoretical way to describe trends within more advanced civilizations, along with a specific description of different civilization types.

Type I

Researcher Michio Kaku quotes Dyson as calculating that Earth will achieve a Type I civilization around the year 2200. [10] This estimate is based on a simple extrapolation of the current development rate of Earth's energy budget. However, Kaku has also noted that there are significant hurdles mankind must overcome in time in order for our civilization to reach the higher statuses. A civilization which has not reached Type I status might be subject to the "uranium barrier" (global political and social development are behind technological development), ecological collapse (which would require planetwide policy to solve), ice ages, asteroid collisions and nearby supernovas [11]

Type I Single Planetary Civilization
Early (1016 W to 1019 W) Middle (1020 W to 1023 W) Late (1024 W to 1026 W) (debatable)
near space colonization, near space industry, Asteroid mining, Planet Mining for fuels and energy [12]

Kaku: "Mark Twain once said, "Everyone complains about the weather, but no one does anything about it." This may change with a Type I civilization, which has enough energy to modify the weather. They also have enough energy to alter the course of earthquakes, volcanoes, and build cities on their oceans." [10]

First Interstellar travel [12] Stress caused by size of civilization, at this point it can fragment into multiple planetary civilizations—reversion from single civilization early in type 1.[13] Construction begins on a Dyson Sphere, Alderson disk, or Ringworld.
Trends:
Increasing levels of technology, Increasing levels of space exploration, space based energy sources increase, offworld civilization centers increase, increasing energy usage, increasing area of habitation
Decreasing levels of centrality, societies and civilizations increasingly are not the same, due to time differences breaking single social bonds [13]. The Nemesis extinction factor (every 26 million years), nearby supernovae, and the death of the Sun can threaten civilizations at these levels [11].

Type II

According to Kaku, Kardaschev has estimated the development of such a civilization at the year 5200, based on the assumption that energy usage grows exponentially at 1% per year. [10]

Type II Civilization has extended to the entire Solar System[9]
Early (1026 W to 1029 W) Middle (1030 W to 1033 W) (debatable) Late (1034 W to 1036 W) (debatable)
Dyson Sphere completion, Exploration and colonization of nearby star systems.[9] Active SETI programs [12] [3] star lifting and Shkadov thrusters, Planck scale particle accelerators [10] Stress caused by size of civilization, at this point it can fragment into multiple solar system based civilizations—reversion to single star based civilization early, Automated galactic or intergalactic colonization effort may begin[3] using von Neumann probes [10]
Trends:
Increasing levels of technology, Exponential growth in stars that are colonized, centralized systems increasingly draw resources from further systems which have not had their resources harvested–– driving increased expansion
Decreasing levels of centrality, increasing likelihood of fragmentation into single star systems if resources cannot be adequately transferred from central sources, resource based wars may reemerge after disappearance during Type I. The death of the galaxy can threaten civilizations at these levels. [11]

Type III

According to Kaku, Kardaschev has estimated the development of such a civilization at the year 7800. However, Dyson has argued that relativity "may delay the transition to a Type III civilization by perhaps millions of years" due to the light speed limit. [10] Since our Milky Way galaxy is approximately 40,000-50,000 light years in radius, and our sun is about 25,000 light years from the galaxy's center, it would take at least 65,000-75,000 years for our civilization to reach every part of the galaxy if no way around the light speed limit can be found.

Type III Colonization of the Milky Way Galaxy has completed
Early (1036 W to 1039 W) (debatable) Middle (1040 W to 1043 W) (debatable) Late (1044 W to 1046 W) (debatable)
(Continued) colonization of nearby galaxies. Highly hypothetical at this point, there are no proposals for this or higher levels.
Trends:
Increasing levels of technology, centralized systems increasingly draw resources from further systems which have not had their resources harvested–– driving increased expansion
Slow growth in galaxies that are colonized due to speed limitations, making centrality impossible.

Current values

International Energy Agency World Energy Outlook past and projected values for planetary power production yield these corresponding Kardashev scale estimates:

Year Energy production Fractional Kardashev
scale equivalent
exajoules/year terawatts Quads[14] mtoes[15]
1900 21 .67 20 500 0.58
1970 190 6.0 180 4500 0.68
1973 260 8.2 240 6200 0.69
1985 290 9.2 270 6900 0.70
1989 320 10 300 7600 0.70
1993 340 11 320 8100 0.70
1995 360 12 340 8700 0.71
2000 420 13 400 10000 0.71
2001 420 13 400 10000 0.71
2002 430 14 410 10400 0.71
2004 440 14 420 10600 0.72
2010 510 16 480 12100 0.72
2030 680 22 650 16300 0.73

Literature describing different Kardashev Types

These categorizations are not firm, and are neither complete nor absolute. Most science fiction space opera writers do not specifically write their works with Kardashev classification in mind. Isaac Asimov's short story The Last Question covers many of the same themes as Kardashev's papers, in its descriptions of the future use of energy and entropy by human civilization; however it does not mention the scale, as it was written in 1956.

Connections with sociology and anthropology

Kardashev's theory can be viewed as the expansion of some social theories, especially from social evolutionism. It is close to the theory of Leslie White, author of The Evolution of Culture: The Development of Civilization to the Fall of Rome (1959). White attempted to create a theory explaining the entire history of humanity. The most important factor in his theory is technology: Social systems are determined by technological systems, wrote White in his book, echoing the earlier theory of Lewis Henry Morgan. As measure of society advancement he proposed the measure energy consumption of a given society (thus his theory is known as energy theory of cultural evolution). He differentiates between five stages of human development. In the first stage, people use energy of their own muscles. In the second stage, they use energy of domesticated animals. In the third stage, they use the energy of plants (which White refers to as agricultural revolution). In the fourth stage, they learn to use the energy of natural resources - such as coal, oil and gas. Finally, in the fifth stage, they harness nuclear energy. White introduced a formula P=E×T, where P measures the advancement of the culture, E is a measure of energy consumed, and T is the measure of efficiency of technical factors utilising the energy.

Notes

  1. ^ http://unesdoc.unesco.org/images/0005/000508/050863fo.pdf in French
  2. ^ A more controversial discussion can be found at "Exotic Civilizations: Beyond Kardaschev". Future Hi. April 15 2004. Retrieved 2006-04-08. {{cite web}}: Check date values in: |year= (help)
  3. ^ a b c Freitas Jr., Robert A. (1980). "INTERSTELLAR PROBES: A NEW APPROACH TO SETI". Journal of the British Interplanetary Society. 33: 95–100.
  4. ^ Galantai, Zoltan (September 7 2003). "Long Futures and Type IV Civilizations" (PDF). Retrieved 2006-05-26. {{cite web}}: Check date values in: |year= (help)
  5. ^ Milan M. Ćirković (February 2004). "Forecast for the Next Eon : Applied Cosmology and the Long-Term Fate of Intelligent Beings". Foundations of Physics. 34. Springer Netherlands: 239-261. doi:10.1023/B:FOOP.0000019583.67831.60. ISSN (Print) 1572-9516 (Online) 0015-9018 (Print) 1572-9516 (Online). {{cite journal}}: Check |issn= value (help)
  6. ^ Kardashev, Nikolai (1985). "On the Inevitability and the Possible Structures of Supercivilizations" in "The search for extraterrestrial life: Recent developments; Proceedings of the Symposium, Boston, MA,June 18-21, 1984". p. 497-504.
  7. ^ Kardashev, Nikolai (March 1997). "Cosmology and Civilizations". Astrophysics and Space Science. 252.
  8. ^ Kardashev, Nikolai (1964). "Transmission of Information by Extraterrestrial Civilizations". Soviet Astronomy. 8: 217.
  9. ^ a b c Freitas Jr., Robert A. Energy and Culture.
  10. ^ a b c d e f Kaku, Michio (2004). "How Advanced Could They Be?". Astrobiology Magazine. {{cite journal}}: Unknown parameter |month= ignored (help), an interview with Michio Kaku.
  11. ^ a b c Kaku, Michio. Hyperspace: A Scientific Odyssey Through Parallel Universes, Time Warps, and the Tenth Dimension. New York: Oxford University Press, 1994. ISBN 0-19-286189-1
  12. ^ a b c Detectability of Extraterrestrial Activities, by Guillermo A Lemarchand
  13. ^ a b Crawford, Ian (2000). "Where Are They?". Scientific American. {{cite journal}}: Unknown parameter |month= ignored (help)
  14. ^ Quads: 1 quadrillion BTU
  15. ^ mtoes: million tonnes (metric tons) of oil equivalents

See also

References

External links

Template:Energy and Sustainability Status Template:Sustainability and energy development group