[...]... detailed description of the adjustment has been published by Mohr and Taylor of the National Institute of Standards and Technology, Gaithersburg, in [1.1] The editors of this Handbook, H Warlimont and W Martienssen, would like to express their sincere thanks to Mohr and Taylor for kindly putting their data at our disposal prior to publication in Reviews of Modern Physics These data first became available... methods of measurements, and work on standards and units, as well as reports concerning the activities, decisions, and recommendations of the various bodies created under the Convention du Mètre 1.2.2 Physical Quantities Physical quantities are tools which allow us to specify and quantify the properties of physical objects and to model the events, phenomena, and patterns of behavior of objects in nature and. .. which are considered as base quantities are a matter of expediency; in different fields and applications of physics, it might well be expedient to use different numbers of base quantities and different selections of base quantities It should be kept in mind, however, that the number and selection of base quantities are only a matter of different representations of physics; physics itself is not affected... to relate this quantity “amount of substance” to a more easily measurable quantity, the mass of a sample of that substance On the basis of an agreement between the International Union of Pure and Applied Physics (IUPAP) and The International System of Units (SI), Physical Quantities, and Their Dimensions 1.2.3.7 Unit of Luminous Intensity: the Candela The base unit candela allows one to establish a... accessibility of data of importance to science and technology The CODATA task group on fundamental constants, established in 1969, has taken on the job of periodically providing the scientific and technological community with a self-consistent set of internationally recommended values of the fundamental constants based on all relevant data available at given points in time What is the meaning of “recommended... with mass number 12 (carbon-12, 12 C) The scale of the masses of all other atoms and isotopes based on this agreement has been called, since then, the scale of relative atomic masses It remains to define the unit of the “amount of substance” in terms of the mass of the corresponding amount of the substance This is done by fixing the mass of a particular amount of carbon-12; by international agreement, this... area of the detector Because of experimental difficulties in realizing a Planckian radiator at high temperatures and because of new possibilities in the measurement of optical radiation power, the 16th CGPM in 1979 adopted a new definition of the candela as follows: The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540 × 1012 hertz and. .. years by the CODATA task group mentioned above The resulting set of best-fit values is then called the “CODATA recommended values of the fundamental constants” based on the adjustment of the appropriate year The tables in Sect 1.1.2 show the CODATA recommended values of the fundamental constants of science and technology based on the 2002 adjustment This adjustment takes into account all data that became... represent a constituent of the world which is absolutely permanent On the basis of this expected invariance of the fundamental constants in space and time, it appears reasonable to relate the units of measurement for physical quanti- ties to fundamental constants as far as possible This would guarantee that also the units of measurement become independent of space and time and of environmental conditions... 25 14 14 14 1.2.1 The International System of Units (SI) All data in this handbook are given in the International System of Units (Système International d’Unités), abbreviated internationally to SI, which is the modern metric system of measurement and is acknowledged worldwide The system of SI units was introduced by the General Conference of Weights and Measures (Conférence Générale des Poids et . alt="" Springer Handbook of Condensed Matter and Materials Data Springer Handbook provides a concise compilation of approved key information on methods of research, general principles, and functional. Heidelberg Printing and binding: Stürtz Würzburg Printed on acid-free paper SPIN 10678245 62/3141/ 5 4 3 2 1 0 GmbH, V Preface The Springer Handbook of Condensed Matter and Ma- terials Data is the realization of. overview and easy retrieval of essential reliable key information, including tables, graphs, and bibli- ographies. References to extensive sources are provided. 123 Handbook Springer of Condensed Matter