In science, a
processthat is not reversible is called irreversible. This concept arises most frequently in thermodynamics, as applied to processes. Irreversibility is also used in economicsto refer to investment or expenditures that involve large sunk costs. [http://links.jstor.org/sici?sici=0022-0515(199109)29%3A3%3C1110%3AIUAI%3E2.0.CO%3B2-I R. S. Pindyck "Irreversibility, Uncertainty, and Investment", Journal of Economic Literature, Vol. 29, No. 3 (Sep., 1991), pp. 1110-1148]
From a thermodynamics perspective, all natural processes are irreversible. The phenomenon of irreversibility results from the fact that if a
thermodynamic systemof interacting molecules is brought from one thermodynamic stateto another, the configuration or arrangement of the atoms and molecules in the system will change as a result. A certain amount of "transformation energy" will be used as the molecules of the "working body" do work on each other when they change from one state to another. During this transformation, there will be a certain amount of heat energy loss or dissipationdue to intermolecular friction and collisions; energy that will not be recoverable if the process is reversed.
Absolute versus Statistical reversibility
Thermodynamics defines the statistical behaviour of large numbers of entities, whose exact behavior is given by more specific laws. Since the fundamental laws of physics are all time-reversible, [ [http://www.isepp.org/Pages/01-02%20Pages/Albert.html David Albert on "Time and Chance"] ] it can be argued that the irreversibility of thermodynamics must be statistical in nature, that is, that it must be merely highly unlikely, but not impossible, that a system will lower in entropy.
The German physicist
Rudolf Clausius, in the 1850s, was the first to mathematically quantify the phenomenon of irreversibility in nature through his introduction of the concept of entropy. In his 1854 memoir “On a Modified Form of the Second Fundamental Theorem in the Mechanical Theory of Heat” Clausius states:
The difference between reversible and irreversible events has particular explanatory value in
complex systems(such as living organisms, or ecosystems). According to the biologists Humberto Maturanaand Francisco Varela, living organisms are characterized by autopoiesis, which enables their continued existence. More primitive forms of self-organizing systems have been described by the physicist and chemist Ilya Prigogine. In the context of complex systems, events which lead to the end of certain self-organising processes, like death, extinction of a species or the collapse of a meteorological system can be considered as irreversible. Even if a clone with the same organizational principle (e.g. identical DNA-structure) could be developed, this would not mean that the former distinct system comes back into being. Events to which the self-organizing capacities of organisms, species or other complex systems can adapt, like minor injuries or changes in the physical environment are reversible. However, adaptation depends on import of negentropyinto the organism, thereby increasing irreversible processes in its environment. Ecological principles, like those of sustainabilityand the precautionary principlecan be defined with reference to the concept of reversibility.
Entropy (arrow of time)
Reversible process (thermodynamics)
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См. также в других словарях:
Irreversibility — Ir re*vers i*bil i*ty, n. The state or quality of being irreversible; irreversibleness. [1913 Webster] … The Collaborative International Dictionary of English
irreversibility — noun The quality of being irreversible; the lack of an ability to be reversed. Now if the irreversibility of Gods gifts to his people, be considered, what joy for those who feel within a wicked heart … Wiktionary
irreversibility — negrįžtamumas statusas T sritis fizika atitikmenys: angl. irreversibility vok. Irreversibilität, f rus. необратимость, f pranc. irréversibilité, f; non réversibilité, f … Fizikos terminų žodynas
irreversibility — irreversible ► ADJECTIVE ▪ impossible to be reversed or altered. DERIVATIVES irreversibility noun irreversibly adverb … English terms dictionary
irreversibility — noun see irreversible … New Collegiate Dictionary
irreversibility — See irreversible. * * * … Universalium
irreversibility — n. quality of being irreversible, quality of being unchangeableirÂ·reÂ·versÂ·iÂ·bilÂ·iÂ·ty || ÉªrÉªâ€švÉœrsÉ™ bÉªlÉ™tÉª / vÉœËs … English contemporary dictionary
irreversibility — ir·reversibility … English syllables
irreversibility — noun the quality of being irreversible (once done it cannot be changed) • Ant: ↑reversibility • Derivationally related forms: ↑irreversible • Hypernyms: ↑changelessness, ↑unchangeability, ↑unchangeableness, ↑ … Useful english dictionary
irreversibility rule — see Dollo s rule … Dictionary of invertebrate zoology