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Field axioms

Exercise 1.21 Show that multiplication of equivalence classes of functions (as defined in Section 1.7) is well defined. Show that addition and multiplication of equivalence classes of functions satisfy some but not all the standard field axioms (such as the distributive law, existence ofO, etc.). The list of field axioms is available in many texts, including [Ru76, Definition 1.12]. Which axioms hold, and which fail ... [Pg.40]

It is an axiom of modern organometallic chemistry that the pursuit of late transition metal complexes is ultimately driven by the need to formulate ever more efficient catalysts and reagents for chemical synthesis. In this respect, the field of poly(pyrazolyl)borate chemistry is no different from any other, albeit that in the case of the group 10 triad the breadth of study is perhaps more limited than for other metals and/or ligands. This section provides an overview of prominent results in respect of both catalysis and the C—H activation processes that underpin them. [Pg.193]

A coalgebra is a fc-space C with maps A C - C C and e C - k satisfying the coassociativity and counit axioms of Hopf algebras. Prove that over a field k any coalgebra is a directed union of finite-dimensional subcoalgebras. [Pg.36]

All macroscopic aspects of the statics and dynamics of electromagnetic field in the presence of material media are described by Maxwell s equations. The differential form of these axioms in the International System of Units (SI) or rationalized MKS system (Cohen and Giacomo, 1987 Lide, 1991) is given in... [Pg.125]

Pontjagin s theorem is as follows [22]. Let T be a locally compact, connected topological field satisfying the second axiom of countability. Then T is isomorphic with one of the three topological fields (1) the held of real numbers, (2) the held of complex numbers, and (3) the held of quaternions. [Pg.694]

Undoubtedly, the axiom that the constraints of the multistep synthesis experience provide the impetus for reaction development will continue to be pertinent to the Diels-Alder reaction. The realization of more reactive and more general catalysts will continue to be a goal for the field and will yield an ever-growing arsenal of tools for use in the synthetic endeavors which require highly functionalized, enantioenriched carbocyclic building blocks. [Pg.1163]

The root of the problem lies in the reasonable assumption that the axioms of Euclidean geometry are equally valid on both cosmic and microscopic scales. It is now known to break down in both instances. Discovery of the electromagnetic field has shown that the familiar ideas on interaction between mass points need adjustment at both large and small separations, where they lead to singularities. Any cosmology that fails to recognize these complications must fail. [Pg.427]

Major scientific theories are, then, created by efforts of human imagination they are created like works of art. The development of the theories into a particular field involves patient work, thought and experimentation, as Popper suggests. The fundamental hypotheses or axioms are obviously synthetic as defined in Section 2.1 and are a posteriori to observation and thought. However, if these hypotheses are used to deduce other results, that deductive process is analytic as we shall now discuss. [Pg.31]

All science is based on a number of axioms (postulates). Quantum mechanics is based on a system of axioms that have been formulated to be as simple as possible and yet reproduce experimental results. Axioms are not supposed to be proved, their justification is efficiency. Quantum mechanics, the foundations of which date from 1925-26, still represents the basic theory of phenomena within atoms and molecules. This is the domain of chemistry, biochemistry, and atomic and nuclear physics. Further progress (quantum electrodynamics, quantum field theory, elementary particle theory) permitted deeper insights into the structure of the atomic nucleus, but did not produce any fundamental revision of our understanding of atoms and molecules. Matter as described at a non-relativistic quantum mechanics represents a system of electrons and nuclei, treated as point-like particles with a definite mass and electric charge, moving in three-dimensional space and interacting by electrostatic forces. This model of matter is at the core of quantum chemistry. Fig. 1.2. [Pg.15]

The temporal and spatial evolutions of the above five fields are determined by so-called balance equations (abbr. balances) for mass, momentum and energy. These equations represent axioms and read ... [Pg.77]

For any prediction, values or interpretations of the variables in the axioms are searched by logical operations a kind of machine reasoning, based on FOPC is utilized for the purpose. A rough comparison of the fields and operations involved in the two approaches is given in SCHEME 1, whileasummary of the FOT-based formal system can be found in APPENDIX I. [Pg.72]

This fundamental principle of physics is given by the axiom of Remark 3.1 in its most general formulation, where SW is the total virtual work of the system. For mechanical fields in deformable structures as well as for electrostatic fields in dielectric domains, it can be restated by the equality of internal 51A and external 6V contributions. [Pg.31]

Here is the virtual work of external charges, and the virtual work of internal charges. As the contained virtual electric field strength vector 8E is assembled from derivatives of the virtual electric potential Sip, the latter has to be continuously differentiable. Further on, the virtual electric potential has to comply with the actual conductive boundary conditions of Eq. (3.36). The initial axiom of Remark 3.1 may now be reformulated for the virtual electric potential. [Pg.35]

A.l. At any time t, for all motions x of the body B there are a local current configuration (l.c.c.) K and the i.s.v. (a,E) where the scalar field a represent tlie dislocation density related to and the symmetric tensor z is the Piola-Kirchhoff type back stress related also to K, with the properties that will be specified further on under the axioms and definitions. [Pg.247]

Core-valence correlation involves the interaction between the inner shell (core) and valence electrons. That this interaction is small is an important axiom of chemistry, as it is well established that the properties of atoms and molecules are largely determined by the valence electrons. This principle underlies the explanation of chemical periodicity and the structure of the periodic table. Conceptually, one considers the inner electrons to be tightly bound and rather inert. Hence, most theoretical studies only consider valence electron correlation with the core electrons frozen at the Hartree-Fock (HF) or multi-configuration self-consistent field (MCSCF) level or replaced with a pseudopotential. The utility and accuracy of the vast body of quantum chemical calculations provide ample evidence justifying this assumption. [Pg.581]


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Axioms

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