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Physical formalisms

This book is intended to mitigate these doubts. There is already enough of a structure to the theory of CA to show that they provide an effective and practical basis for the treatment of specific, as well as general, questions. In this monograph, the physical, formal and mathematical framework will be systematized to such an extent, that the framework becomes the natural setting for an effective description of the natural world. Just to what extent the fundamental laws of physics can, or... [Pg.839]

The whole enterprise of Quantum chemistry, myriads of Gigaflops of computational resources for decades have been absorbed with Dirac s is only. Not only do physicists and chemists start at different points, they start in different races. For a theoretical physicist it simply does not matter that there is not a single molecule in the whole universe to which the quantum physical formalism is applicable. Yet for chemistry, at its core a highly taxonomic discipline, a model that cannot be applied anywhere is not a viable model. It is only with a massive set of drastic approximations and assumptions that we can get Quantum chemistry on its way. [Pg.132]

Results of Calculations of NLO Properties and Their Discussion. - 5.2.1 Solid State Physical Calculations. - The calculation of static linear polarizabilities < zz/N = oll/N for the polymers poly(H2), and the H-bonded systems poly(H20) and poly(LiH) using the above described solid state physical formalism has given much larger values116 than those obtained by extrapolating oligomer values with the aid of different procedures. Further computations for... [Pg.494]

Each of these mathematical formalisms, although related to the same physical formalism, facilitate a better understanding of different aspects of a droplet existence (formation, life, and destruction). [Pg.391]

In general, considering the physical fields to which a material is exposed during its synthesis, a strategy similar to that employed for designing materials is possible for synthesis. Therefore, the essential problem is to describe the process by a sufficiently exact model through essential mathematical and physical formalisms. [Pg.524]

Jones R O 1987 Molecular calculations with the density functional formalism Advances in Chemicai Physics vol LXVIl, ed K P Lawley (New York Wiley-Interscience) pp 413-37... [Pg.2198]

Holian B L 1996 The character of the nonequilibrium steady state beautiful formalism meets ugly reality Monte Carlo and Molecular Dynamics of Condensed Matter Systems, vol 49, ed K Binder and G Ciccotti (Bologna Italian Physical Society) pp 791-822... [Pg.2280]

The question of determination of the phase of a field (classical or quantal, as of a wave function) from the modulus (absolute value) of the field along a real parameter (for which alone experimental determination is possible) is known as the phase problem [28]. (True also in crystallography.) The reciprocal relations derived in Section III represent a formal scheme for the determination of phase given the modulus, and vice versa. The physical basis of these singular integral relations was described in [147] and in several companion articles in that volume a more recent account can be found in [148]. Thus, the reciprocal relations in the time domain provide, under certain conditions of analyticity, solutions to the phase problem. For electromagnetic fields, these were derived in [120,149,150] and reviewed in [28,148]. Matter or Schrodinger waves were... [Pg.104]

In addition, it can occasionally be useful to regard some physical parameter appearing in the theoi y as a complex quantity and the wave function to possess analytic properties with regard to them. This formal procedure might even include fundamental constants like e, h, and so on. [Pg.110]

Lead, like tin, forms only one hydride, plumbane. This hydride is very unstable, dissociating into lead and hydrogen with great rapidity. It has not been possible to analyse it rigorously or determine any of its physical properties, but it is probably PbH4. Although this hydride is unstable, some of its derivatives are stable thus, for example, tetraethyllead, Pb(C2Hj)4, is one of the most stable compounds with lead in a formal oxidation state of + 4. It is used as an antiknock in petrol. [Pg.177]

Gunnarsson O and B I Lundqvist 1976. Exchange and Correlation in Atoms, Molecules, and Solids by the Spin-density-functional Formalism. Physical Review B13.-4274-4298. [Pg.181]

In the main, the physical and chemical properties of saturated and partially unsaturated alicyclic compounds closely resemble those of the analogous acyclic compounds formally derived by cleavage of the carbon ring at a point remote from any functionality. Relatively small, but often significant, differences in properties arise from conformational effects, and from strain effects in small rings, and these differences can be striking in properties which are particularly sensitive to molecular shape. [Pg.2]

To gain physical insight into the asymmetric situation let us compare Miller s result (3.81) with that obtained by considering a formal two-state problem with the matrix Hamiltonian,... [Pg.53]

It is to be emphasized that, despite the formal similarity, the physical problems are different. Moreover, in general, diabatic coupling is not small, unlike the tunneling matrix element, and this circumstance does not allow one to apply the noninteracting blip approximation. So even having been formulated in the standard spin-boson form, the problem still remains rather sophisticated. In particular, it is difficult to explore the intermediate region between nonadiabatic and adiabatic transition. [Pg.92]

While 1 was in Argentina in 1955, Sabato took me to visit a brand new laboratory in Patagonia, deep in the south , near the ski resort of San Carlos de Bariloche. This was, and still is, the Centro Atomico de Bariloche (CAB). It is an institution (formally part of a local university) for research and teaching in physics, ranging from particle physics to solid-state physics. Its origin is one of the most curious in the entire history of academe. [Pg.529]

HAZOP is a formal technique for eliciting insights about system behavior from a multidisciplinary team that collectively has thorough knowledge of the plant and the physical phenomena involved in the plant (Figure 3.3.4-1). [Pg.86]

The simplified failure envelopes are not derived from physical theories of failure in which the actual physical processes that cause failure on a microscopic level are integrated to obtain a failure theory. We, instead, deal with phenomenological theories in which we ignore the actual failure mechanisms and concentrate on the gross macroscopic events of failure. Phenomenological theories are based on curve-fitting, so they are failure criteria and not theories of any kind (the term theory implies a formal derivation process). [Pg.102]

Suppose we have a physical system with small rigid particles immersed in an atomic solvent. We assume that the densities of the solvent and the colloid material are roughly equal. Then the particles will not settle to the bottom of their container due to gravity. As theorists, we have to model the interactions present in the system. The obvious interaction is the excluded-volume effect caused by the finite volume of the particles. Experimental realizations are suspensions of sterically stabilized PMMA particles, (Fig. 4). Formally, the interaction potential can be written as... [Pg.750]

The PSS columns quality manager inspects each column and certificate for formal and physical correctness. [Pg.290]


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