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Name construction spaces

Intentionally mistating Misner, et.aJ. s quote with which we began this section, one is tempted to speculate, instead, that Neither matter nor space tells the other how to act, for both are nothing other than constructs of information. There is no such thing as spacetime, only information. Sometimes it acts like space, sometimes it acts like matter and sometimes it simultaneously acts as both. In many ways, this would be an ideal marriage between the central lesson of gravity - namely, the proposition that spacetime is not just a static backdrop on top of which dynamics takes place but is an active coupled participant in that dynamics - and the notion that, underneath it all, fundamentally, all is information. [Pg.689]

Estimate (52) indicates an effective reduction of the speed of convergence of scheme (51) on the non-equidistant grid ui), in comparison with scheme (44) on the equidistant grid. However, as we have stated above, if the error of approximation is evaluated not in the grid norm of the spaces C or Ljj but in a specially constructed negative norm ( ip then the error of approximation on any non-equidistant grid will be of the same order 0 h ). Namely, the negative norm... [Pg.115]

Let us take a simple example, namely a generic Sn2 reaction mechanism and construct the state functions for the active precursor and successor complexes. To accomplish this task, it is useful to introduce a coordinate set where an interconversion coordinate (%-) can again be defined. This is sketched in Figure 2. The reactant and product channels are labelled as Hc(i) and Hc(j), and the chemical interconversion step can usually be related to a stationary Hamiltonian Hc(ij) whose characterization, at the adiabatic level, corresponds to a saddle point of index one [89, 175]. The stationarity required for the interconversion Hamiltonian Hc(ij) defines a point (geometry) on the configurational space. We assume that the quantum states of the active precursor and successor complexes that have non zero transition matrix elements, if they exist, will be found in the neighborhood of this point. [Pg.321]

In literature the above diagnostic measures are known under different names. Instead of the score distance from Equation 3.27 which measures the deviation of each observation within the PCA space, often the Hotelling T2-test is considered. Using this test a confidence boundary can be constructed and objects falling outside this boundary can be considered as outliers in the PCA space. It can be shown that this concept is analogous to the concept of the score distance. Moreover, the score distances are in fact Mahalanobis distances within the PCA space. This is easily... [Pg.94]

The continuous wavelet transform (WT) is a space-scale analysis that consists in expanding signals in terms of wavelets that are constructed from a single function, the analyzing wavelet /, by means of dilations and translations [13, 27-29]. When using the successive derivatives of the Gaussian function as analyzing wavelets, namely... [Pg.209]

A coordinate system is a mathematical device for naming positions in space. From the geometric standpoint, a coordinate system is an artificial construct, because the structure of an object is defined by the relationships between its component parts, independent of any external references. Nevertheless a description of geometric objects by means of a coordinate system is a convenient way to describe numerically the internal structure of an object and the relationships between different positions and orientations of an object in space. [Pg.23]

Since, in this causal model, the extended wave 0 represents a real physical finite wave with well-defined energy, it seems natural to represent it by a suitable mathematical form. At the time when de Broglie put forth his causal interpretation of quantum mechanics, it was necessary for him to construct a finite wave using the Fourier analysis, namely, the multiplicity of harmonic plane waves, infinite in space and time, summing up and giving origin to a wavepacket. [Pg.507]

Mathematical approximations to the periodic minimal surfaces can be constructed from terms which are each the result of adding symmetry-related sinusoidal density waves for the appropriate symmetry group, and then taking the nodal surface the boundary between regions of positive and of negative density. The waves that correspond to a face-centred figure in real space are the body-centred terms in reciprocal space, namely ... [Pg.119]

The notation concerns are easily overcome by the following simple construct bearing the name of second quantization formalism.21 Let us consider the space of wave functions of all possible numbers of electrons and complement it by a wave function of no electrons and call the latter the vacuum state vac). This is obviously the direct sum of subspaces each corresponding to a specific number of electrons. It is called the Fock space. The Slater determinants eq. (1.137) entering the expansion eq. (1.138) of the exact wave function are uniquely characterized by subsets of spin-orbitals K = k,, k2,..., fc/v which are occupied (filled) in each given Slater determinant. The states in the list are the vectors in the carrier space of spin-orbitals (linear combinations of the functions of the (pk (x) = ma (r, s) basis. We can think about the linear combinations of all Slater determinants, may be of different numbers of electrons, as elements of the Fock space spanned by the basis states including the vacuum one. [Pg.54]

We would like to emphasize that, due to the closure constraint, there are only (m — 1) linearly independent internal MEC. Thus, the m vectors defined by Eq. (93) in reality span the (m — 1 )-dimensional space of internal MEC. In order to remove this linear dependence one could adopt the relative internal approach of Sect. 2.1.3. Namely, one then selects the electron population of one atom in the system as dependent upon populations of all remaining atoms, and discards the MEC associated with that atom. All remaining MEC can also be constructed directly from the corresponding internal relative softness matrix. Although the sets of independent internal MEC for alternative choices of the dependent atom will differ from one another, they must span the same (m — 1 )-dimensional linear space of independent internal MEC. For example, in the two-AIM system of Fig. 4 there is only one independent internal MEC direction along the P-line. [Pg.52]


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See also in sourсe #XX -- [ Pg.30 ]




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