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accelerator:see particle acceleratorparticle accelerator,
apparatus used in nuclear physics to produce beams of energetic charged particles and to direct them against various targets. Such machines, popularly called atom smashers, are needed to observe objects as small as the atomic nucleus in studies of its
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in modern bourgeois macroeconomics, the ratio of the increase in investments to the relative increment in income, consumer demand, or finished product causing this increase. The accelerator is expressed by the formula
(where I = investments, Y = income, t = time). It is used as a quantitative expression of the “acceleration principle,” according to which any increase or reduction in income, demand, or product causes (or requires) a relatively greater (percentage-wise) increase or reduction in the “induced” investments. This principle, which was proposed by A. Aftalion in 1913 and J. M. Clark in 1919, was subsequently elaborated in greater detail by the Englishmen R. Harrod and J. Hicks and the American P. Samuelson. It has been included in the neo-Keynesian models of economic growth.
The reasons for the sharper dynamics in the increments or reductions in investments, in comparison with the income or demand dynamics causing them, are to be found in the duration of the equipment manufacturing time. Therefore, in the period between the development of demand for additional equipment and its output, the unsatisfied demand impels an expansion of production beyond the limit of the initial demand. Another factor is the duration of the use of equipment. As a consequence of this, the percentage of new investments to replacement investments is greater than the percentage increase of product, the demand for which caused the new investments. For example, if, with a fixed capital of $500 million of which 10 percent wears out annually ($50 million), demand for finished goods increases by 10 percent, the investments are required to compensate not only for the wear on fixed capital but also for the additional expansion of capital to satisfy the increased demand (by $50 million). A mere 10 percent increase in the demand for finished products causes a doubling of gross investments for equipment.
In macroeconomic models, the accelerator is combined with the multiplier in the form of the Hicks national income equation:
Yt = At + (1–s)Yt−1 + v (Yt−1 – Yt−2)
where A = autonomous investments and (1–s) = the share of consumption in national income or its increase. Depending on the multiplier factor, or the coefficient of the inclination to consume, and the accelerator, the dynamics of national income (Y) or its increases can assume an even or cyclical character. Cyclical fluctuations arise with a ratio
[(1–s) + v]2 < 4v
Thus, the accelerator principle is viewed by bourgeois economists as one of the main explanations for economic cycles.
The rational elements of the accelerator concept consist of certain technical proportions between the replacement and expansion of fixed capital and the depiction of turning points in investment dynamics moving from one phase of the cycle to another. The fundamental failings of the concept are the substitution of technical dependencies in the process of fixed capital reproduction for the real causes of the capitalist cycle; the erroneous notion of investment dynamics as a function of income and consumer demand, while with capitalism these dynamics are determined by the drive for profit; the contradiction between the acceleration principle and the real process of the reduction in the capital intensiveness of product; and the rejection of opportunities to satisfy demand without additional investments by the fuller loading of equipment and the intensification of its utilization. Like all models in bourgeois macroeconomics, the accelerator model reflects only certain external functional relationships and ignores the actual cause-and-effect dependencies of the reproduction process.
REFERENCESSamuelson, P. Ekonomika: Vvodnyi kurs. Moscow, 1964. Pages 289–303. (Translated from English.)
Al’ter, L. B. “Modeli mul’tiplikatora i akseleratora v mak-roekonomicheskoi dinamike.” In the collection Kapitalisticheskoe vosproizvodstvo v sovremennvkh usloviiakh. Moscow, 1966. Pages 107–128.
Al’ter, L. B. Burzhuaznaia politicheskaia ekonomiia SShA, ch. 13, pp. 593–609. Moscow, 1961.
Hansen, A. H. Business Cycles and National Income. New York, 1951.
Clark, J. M. “Business Acceleration and the Law of Demand.” In Readings in Business Cycle Theory, part 3. Philadelphia-Toronto, 1944.
L. B. AL’TER
accelerator(1) See particle accelerator.
(2) Speeding up the retrieval of Web pages. See Web page acceleration and CDN.
(3) Speeding up file downloading. See download accelerator.
(4) Speeding up hardware. See graphics accelerator, video accelerator and accelerator board.
(5) A quick way to gain knowledge when reading text on a Web page. For example, after highlighting a word and clicking a button, an accelerator may provide a dictionary definition, a foreign language translation or the map of a street address.
(6) A key combination such as Alt-Shift-G that is used to activate a task. It provides a faster activation method than selecting from a menu. See also special function key.
(7) An incubator that expects to develop the company considerably faster than normal. See incubator.