The Kardashev scale is a method of measuring civilization's levelof technological advancement, based on the amount of energy a civilization is able to utilize. The scale has three designated categories called Type I, II, and III. A Type I civilization uses all available resources impinging on its home planet, Type II harnesses all the energy of its star, and Type III of its galaxy. The scale is only hypothetical, but it puts energy consumption in a cosmic perspective. It was first proposed in 1964 by the Soviet astronomer Nikolai Kardashev. Various extensions of the scale have been proposed since, from a wider range of power levels (types 0, IV and V) to the use of metrics other than pure power. In 1964, Kardashev defined three levels of civilizations, based on the order of magnitude of power available to them:
Type I
"Technological level close to the level presently attained on earth, with energy consumption at ≈4×1019 erg/sec (4 × 1012 watts.) Guillermo A. Lemarchand stated this as "A level near contemporary terrestrial civilization with an energy capability equivalent to the solar insolation on Earth, between 1016 and 1017 watts
Type II
"A civilization capable of harnessing the energy radiated by its own star (for example, the stage of successful construction of aDyson sphere), with energy consumption at ≈4×1033 erg/sec.[1] Lemarchand stated this as "A civilization capable of utilizing and channeling the entire radiation output of its star. The energy utilization would then be comparable to the luminosity of our Sun, about 4 × 1026 watts
Type III
"A civilization in possession of energy on the scale of its own galaxy, with energy consumption at ≈4×1044 erg/sec."[1] Lemarchand stated this as "A civilization with access to the power comparable to the luminosity of the entire Milky Way galaxy, about 4 × 1037Watts
Michio Kaku suggested that humans may attain Type I status in 100–200 years, Type II status in a few thousand years, and Type III status in 100,000 to a million years.
In 2008, total world energy consumption was 474 exajoules (474×1018 J=132,000 TWh), equivalent to an average power consumption of 15 TW (or 0.717 on Sagan's Kardashev scale).
There are many historical examples of human civilization undergoing large-scale transitions, such as the Industrial Revolution. 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[16] suggests that the transition from Type 0 to Type I might carry a strong risk of self-destruction since, in some scenarios, there would no longer be room for further expansion on the civilization's home planet, as in a Malthusian catastrophe. Excessive use of energy without adequate disposal of heat, for example, could plausibly make the planet of a civilization approaching Type I unsuitable to the biology of the dominant life-forms and their food sources. If Earth is an example, then sea temperatures in excess of 35 C would jeopardize marine life and make the cooling of mammals to temperatures suitable for their metabolism difficult if not impossible. Of course, these theoreticalspeculations may not become problems in reality thanks to evolution or the application of future engineering and technology. Also, by the time a civilization reaches Type I it may have colonized other planets or created O'Neill-type colonies, so that waste heat could be distributed throughout the solar system.
Many extensions and modifications to the Kardashev scale have been proposed. The most straightforward extend the scale to even more hypothetical Type IV beings who can control or use the entire universe or Type V who control collections of universes. The energy output of the visible universe is within a few orders of magnitude of 1045 W. 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. Zoltan 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) Milan M. Ćirković has argued that "Type IV" should instead refer to a civilization that has harnessed the power of its supercluster, or "the largest gravitationally bound structure it originated in. For the Local Supercluster, this would be approximately 1042 W.
In his book Parallel Worlds, Michio Kaku has discussed a Type IV civilization that could harness "extragalactic" energy sources such as dark energy. Other proposed changes to the scale use different metrics such as 'mastery' of systems, amount of information used, or progress in control of the very small as opposed to the very large. Metrics other than pure power usage have also been proposed. One is 'mastery' of a planet, system or galaxy rather than considering energy alone Alternatively, Carl Sagan suggested adding another dimension in addition to pure energy usage: the information available to the civilization. He assigned the letter A to represent 106 unique bits of information (less than any recorded human culture) and each successive letter to represent an order of magnitude increase, so that a level Z civilization would have 1031 bits. In this classification, 1973 Earth is a 0.7 H civilization, with access to 1013 bits of information. Sagan believed that no civilization has yet reached level Z, conjecturing that so much unique information would exceed that of all the intelligent species in a galactic supercluster and observing that the universe is not old enough to exchange information effectively over larger distances. The information and energy axes are not strictly interdependent, so that even a level Z civilization would not need to be Kardashev Type Ⅲ
John D. Barrow, going by the fact that humans have found it more cost-effective to extend any abilities to manipulate their environment over increasingly smaller dimensions rather than increasingly larger ones, reverses the classification downward from Type Ⅰ-minus to Type Omega-minus: Type Ⅰ-minus is capable of manipulating objects over the scale of themselves: building structures, mining, joining and breaking solids;Type Ⅱ-minus is capable of manipulating genes and altering the development of living things, transplanting or replacing parts of themselves, reading and engineering their genetic code; Type Ⅲ-minus is capable of manipulating molecules and molecular bonds, creating new materials; Type Ⅳ-minus is capable of manipulating individual atoms, creating nanotechnologies on the atomic scale and creating complex forms of artificial life; Type Ⅴ-minus is capable of manipulating the atomic nucleus and engineering the nucleons that compose it; Type ⅤI-minus is capable of manipulating the most elementary particles of matter (quarks and leptons) to create organized complexity among populations of elementary particles; culminating in. Type Omega-minus is capable of manipulating the basic structure of space and time.According to this scale, human civilization is between III- and IV-minus. Robert Zubrin adapts the Kardashev scale to refer to how widespread a civilization is in space, rather than to its energy use. In his definition, a Type I civilization has spread across its planet, a Type II has extensive colonies in its respective stellar system, and a Type III has colonized its galaxy
From : wikipedia.org
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