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Infinite curvature

Recall the reciprocity between matter and curvature, implied by the theory of general relativity, to argue that the high-pressure condition at Z/N = 1 corresponds to extreme curvature of space-time caused by massive objects such as quasars, and the like. The argument implies that the Schrodinger solution is valid in empty, flat euclidean space-time, that Z/N = r corresponds to the real world, Z/N = 1 occurs in massive galactic objects where elemental synthesis happens, and Z/N > 1 implies infinite curvature at a space-time singularity. [Pg.136]

To obtain isochores whose curvatures become very large, approaching the critical density along the critical isotherm, as required by Equation 1, we have designed an infinite curvature for isochores at an origin, 0(p),... [Pg.349]

Although the Godel solution is free of singularities the need to accommodate black holes in the cosmic model requires an interpretation of the Schwarzschild singularity which occurs with infinite curvature of space-time. A new interpretation is rather obvious. Such a high degree of curvature must clearly rupture the interface between adjacent sides of the postulated cosmic double cover. Rather than disappear into a singularity, the matter,... [Pg.241]

An appropriate set of boundary conditions may be stated in terms of the extrapolated dimensions of the parallelepiped. In the present calculation we will ignore the difficulties in the concept of the extrapolated boundary at the corners which have infinite curvature by arguing that the necessary correction will be small and, furthermore, that the region of primary importance in the reactor is near the center of the block. With this approximation in mind we can confine the requirements on the neutron flux to the following pair of boundary conditions ... [Pg.214]

Equality is forbidden since it yields an infinite curvature the excluded region near by is the core region. [Pg.16]

Star polymers are excellent models for block copolymers dissolved in selective solvents and for end-associating polymers that form polymeric micelles [1,2]. These polymers, with their dense core and swollen corona, are of great technical importance but are difficult to study because their degree of association is highly variable. Knowledge of the properties of stars is also important for the design of the properties of star block copolymers, which are an important class of industrial materials. The conformation of the arms of a star is also the limiting conformation of polymers attached to a surface with infinite curvature (l/R ), Therefore, the properties of star polymers are related to the properties of polymer-coated colloidal particles. [Pg.286]

Bikerman [179] has argued that the Kelvin equation should not apply to crystals, that is, in terms of increased vapor pressure or solubility of small crystals. The reasoning is that perfect crystals of whatever size will consist of plane facets whose radius of curvature is therefore infinite. On a molecular scale, it is argued that local condensation-evaporation equilibrium on a crystal plane should not be affected by the extent of the plane, that is, the crystal size, since molecular forces are short range. This conclusion is contrary to that in Section VII-2C. Discuss the situation. The derivation of the Kelvin equation in Ref. 180 is helpful. [Pg.285]

We note that if the crack opening is zero on F,, i.e. [%] = 0, the value of the objective functional Js u) is zero. We also assume that near F, the punch does not interact with the shell. It turns out that in this case the solution X = (IF, w) of problem (2.188) is infinitely differentiable in a neighbourhood of points of the crack. This property is local, so that a zero opening of the crack near the fixed point guarantees infinite differentiability of the solution in some neighbourhood of this point. Here it is undoubtedly necessary to require appropriate regularity of the curvatures % and the external forces u. The aim of the following discussion is to justify this fact. At this point the external force u is taken to be fixed. [Pg.131]

For a cylindrical vessel, the radius of curvature in the axial direction is infinite, and the stress in the direction of the circumference, called the hoop stress, is... [Pg.194]

In the sections above, only infinite planar interfaces between air and an aqueous phase or two immiscible liquids like water and DCE were considered. Reducing the question to this class of surfaces only would be a severe limitation in the scope of the review as more reports appear in the literature debating on the SH response from small centro-symmetrical particles [107-110]. It is the purpose of this section to discuss the SHG response from interfaces having a radius of curvature of the order of the wavelength of light. [Pg.154]

In the theoretical section above, the nonlinear polarization induced by the fundamental wave incident on a planar interface for a system made of two centrosymmetrical materials in contact was described. However, if one considers small spheres of a centrosymmetrical material embedded in another centrosymmetrical material, like bubbles of a liquid in another liquid, the nonlinear polarization at the interface of a single sphere is a spherical sheet instead of the planar one obtained at planar surfaces. When the radius of curvature is much smaller than the wavelength of light, the electric field amplitude of the fundamental electromagnetic wave can be taken as constant over the whole sphere (see Fig. 7). Hence, one can always find for any infinitely small surface element of the surface... [Pg.154]

The parallel surface method (PSM) has been invented to measure the average interface curvature (and the Euler characteristic) from the 3D data images [222]. First, a parallel surface to the interface is formed by translating the original interface along its normal by an equal distance everywhere on the surface (see Fig. 33). The change of the surface area at the infinitely small parallel shift of the surface is... [Pg.210]

In detail, the surface starts forming an oval under the influence of increasing field strength and in turn, a sharper curvature of the oval increases the field strength. When a certain field strength is reached, the equilibrium of surface tension and electrostatic forces becomes independent of the curvature s radius, and mathematically, the radius could become zero. However, in a real system infinite... [Pg.452]

Hypothetical linear macromolecule consisting of an infinitely thin chain of continuous curvature the direction of curvature at any point is random. [Pg.47]

With short chain derivatives, the forces of repulsion are higher than the ones of attraction the curvature is high and spherical micelles are formed at a concentration called the critical micellar concentration (cmc). This concentration can be detected by a change in the physico-chemical properties of the solution (e.g. surface tension, Fig. 3 a). Above a characteristic temperature (referred as Krafft temperature), the tensio-active molecules are infinitely soluble in the form of micelles (Fig. 3 b). [Pg.280]

Streamline curvature over a very extensive region, and there is infinite drift. On the axis of symmetry, the fluid velocity falls to half the sphere velocity almost two radii from the surface. The corresponding distance for potential flow is 0.7 radii. [Pg.35]

In a pore the overlapping potentials of the walls more readily overcome the translational energy of an adsorbate molecule so that condensation will occur at a lower pressure in a pore than that normally required on an open or plane surface. Thus, as the relative pressure is increased, condensation will occur first in pores of smaller radii and will progress into the larger pores until, at a relative pressure of unity, condensation will occur on those surfaces where the radius of curvature is essentially infinite. Conversely, as the relative pressure is decreased, evaporation will occur progressively out of pores with decreasing radii. [Pg.54]


See other pages where Infinite curvature is mentioned: [Pg.289]    [Pg.29]    [Pg.207]    [Pg.333]    [Pg.304]    [Pg.453]    [Pg.265]    [Pg.433]    [Pg.79]    [Pg.274]    [Pg.101]    [Pg.289]    [Pg.29]    [Pg.207]    [Pg.333]    [Pg.304]    [Pg.453]    [Pg.265]    [Pg.433]    [Pg.79]    [Pg.274]    [Pg.101]    [Pg.438]    [Pg.644]    [Pg.703]    [Pg.733]    [Pg.962]    [Pg.280]    [Pg.155]    [Pg.41]    [Pg.98]    [Pg.204]    [Pg.265]    [Pg.189]    [Pg.200]    [Pg.258]    [Pg.269]    [Pg.26]    [Pg.46]    [Pg.255]    [Pg.89]    [Pg.579]    [Pg.59]   
See also in sourсe #XX -- [ Pg.136 , Pg.290 ]




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Curvatures

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