Physical constants, universal

Sven Otto Pettersson, 1848-1941. Professor of chemistry at the University of Stockholm from 1881-1908. Hydrog-rapher and oceanographer. He collaborated with Lars Fredrik Nilson in researches on metallic titanium and the physical constants of titanium and germanium. He was one of the first chemists to support Svante Arrhenius in his views on electrolytic dissociation. For a discussion of his hydrographic work see ref. (69). 

If a natural or universal physical constant has an impact on the process, it has to be incorporated into the relevant list, whether it will be altered or not. In this context, the greatest mistakes are made with regard to the gravitational constant g. Lord Rayleigh (3) complained bitterly saying ... 

John Barrow and Frank Tipler, in the Anthropic Cosmological Principle, are fascinated by the number of seemingly coincidental conditions, events, and physical constants that guide our Universe. For example, they find the number of coincidences involving 1039 remarkable. 

The relevance list must also include universal physical constants such as the universal gas constant, R, the speed of light in a vacuum, c, or even the acceleration of a gravitational field (on Earth the acceleration due to gravity, g), if these constants influence the process concerned. The fact that a relevant physical quantity is a constant can never be a reason not to include it in the relevance list By failing to consider the relevance of gravitational acceleration, the chemical engineer may find he has made a serious mistake ... 

Fundamental physical constants are universal and their values are needed for different problems of physics and metrology, far beyond the study of simple atoms. That makes the precision physics of simple atoms a subject of a general physical interest. The determination of constants is a necessary and important part of most of the so-called precision test of the QED and bound state QED and that makes the precision physics of simple atoms an important field of a general interest. 

At best, this approach provides a quantitative index to solvent polarity, from which absolute or relative values of rate or equilibrium constants for many reactions, as well as absorption maxima in various solvents, can be derived. Since they reflect the complete picture of all the intermolecular forces acting in solution, these empirical parameters constitute a more comprehensive measure of the polarity of a solvent than any other single physical constant. In applying these solvent polarity parameters, however, it is tacitly assumed that the contribution of intermolecular forces in the interaction between the solvent and the standard substrate is the same as in the interaction between the solvent and the substrate of interest. This is obviously true only for closely related solvent-sensitive processes. Therefore, an empirical solvent scale based on a particular reference process is not expected to be universal and useful for all kinds of reactions and absorptions. Any comparison of the effect of solvent on a process of interest with a solvent polarity parameter is, in fact, a comparison with a reference process. 

The laws of nature and the physical constants were established so that human beings would arise in the universe. 

We live in a biofriendly world. Were it otherwise, we wouldn t be around. The question is, therefore, how biofriendly is it Physicists have addressed this question and have come to the conclusion that if any of the fundamental physical constants were a little smaller or a little larger than they are, the universe would be very different from what it is and unable to produce or harbor living organisms. Not everyone, however, subscribes to the concept of fine-tuning embodied in the so-called Anthropic Principle, some preferring instead the notion of a multiverse, in which our universe is only one in trillions of trillions, perhaps the only one that, by mere chance, happened to have the right combination of constants to enable it to serve as our birthplace and abode. 

The reason is that physicists claims for a finely tuned universe are centered on the assertion of improbable non-randomness. In particular, the handful of physical constants responsible for our universe not only appear finely tuned, but are, as far as we know, unrelated to one another, that is each can be independently set yet each must fall within a particular range to make a universe in which habitable environments... 

We define quantitative scientific knowledge as the combination of numerical data and formulas. A quantity can be a geometrical quantity like area or volume, or a physical quantity like mass or viscosity. A geometrical quantity is a variable which depends on the geometrical shape under consideration. Physical quantities can be categorised into constant properties and variables. Physical constants are the universal constants of nature, such as Boltzmann s constant (k = 1.380658 10-23/A-1). Physical properties are quantities which hold different values for different substances (or elements) in different states, for example, the Critical Volume (m3 mo/-1) 72.5 10-6 of Ammonia. The physical constants and physical properties are held in a database. Physical variables (sometimes called state variables) are independent variables which describe the state of a physical system, such as temperature (T) or pressure (P). The variables (including geometric values) are either specified by a user or computed by the system. 

Frequency measurements, which are amongst the most accurate measurements made, form a basis of, on the one hand, practical measurements of length as defined in terms of the SI metre for example, and on the other, determination of universal physical constants such as the Rydberg constant. Atomic physics lies at the heart of these measurements, providing the tools and methods of laser spectroscopy as well as the theory of atomic structure and atom-light interaction with which to interpret the results of measurements and relate them to other fields of physics. 

A microparticle is defined as a physical object whose wave properties can be registered. This class includes elementary particles, atomic nuclei, atoms (atomic ions), molecules (molecular ions) and more complex assemblies (like clusters and macromolecules). Some properties of microparticles belong to the universal physical constants (energy, mass, linear momentum, angular momentum, electric charge, magnetic moment) some, on the contrary, are exclusively specific for microparticles (spin, parity, life-time). Macroscopic state properties (such as temperature, pressure, volume, entropy, etc.) are irrelevant for a single microparticle. 

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