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Einstein dynamical equation

The term k in this metric is a constant that determines the spacial curvature of the cosmology. For k = 1 the cosmology is a closed spherical universe, for k = 0 the cosmology is flat, and for k - — 1 the cosmology is open. The Einstein field equations give a constraint equation and a dynamical equation for the rate the radius changes with time. If we define a velocity as v = (R/R)H(t)r, where H (t) is the Hubble parameter, a constant locally, the constraint equations is... [Pg.464]

The time dependence of the anisotropy r(t) depends on the underlying dynamics of reorientational motion. For rotational diffusion (tumbling) of a spherical object, the expected anisotropy decay is exponential with a rotational diffusion time given in the hydrodynamic limit by the Stokes-Einstein-Debye equation. For nonspherical molecules, more complex time dependence may be detected. (For more on these topics, see the book by Cantor and Schimmel in Further Reading.)... [Pg.557]

Equation (12) is derived by combining Debye s relation with the hydro-dynamic equation. In (12), is a flow parameter appearing in the Einstein theory. Next, let IV be the energy loss when a system of suspension flows with s. Then, the equation corresponding to (12) is written as... [Pg.283]

Both the Newton/Einstein and Schrodinger/Dirac dynamical equations are differential equations involving the derivative of either the position vector or wave function with respect to time. For two-particle systems with simple interaction potentials V, these can be solved analytically, giving r(t) or F(r,i) in terms of mathematical functions. For systems with more than two particles, the differential equation must be solved by numerical techniques involving a sequence of small finite time steps. [Pg.8]

Figure 9.11 Plot of the mean square displacement (MSD, A ) of water molecules vs time (ps) for 0.6 ns of molecular dynamics at constant pressure. The slope of the curve is 1.2866. Following Einstein s equation, the lateral coefficient of water is one-sixth of this value, i.e., 0.214 AVps or 2.14 X 10 cmVs. In these conditions, the normal value for bulk water is 3.5 x 10 cmVs. In fact a noticeable part of the water is partially trapped into hydration shells around charged moieties like phosphocholines... Figure 9.11 Plot of the mean square displacement (MSD, A ) of water molecules vs time (ps) for 0.6 ns of molecular dynamics at constant pressure. The slope of the curve is 1.2866. Following Einstein s equation, the lateral coefficient of water is one-sixth of this value, i.e., 0.214 AVps or 2.14 X 10 cmVs. In these conditions, the normal value for bulk water is 3.5 x 10 cmVs. In fact a noticeable part of the water is partially trapped into hydration shells around charged moieties like phosphocholines...
A, . 2, polynomial coefficients in Einstein s equation for dynamic viscosity... [Pg.52]

Coarse coal is to be pumped in a mbber lined 18 in pipe steel with an inner diameter of 17 in. A screen analysis of the coal indicates that it has a distrihution of 20% passing 200 mi crons. The velocity of pumping is 4.5 tn/s and the total weight concentration is 52%. The specific gravity of the coal is 1.35. Determine the hydraulic gradient due to wall friction in the horizontal pipeline. Assume a water dynamic viscosity of 1.2 cP, but correct for viscosity due to solids using Einstein s equation. Assume a drag coefficient of 0.75 for the coarse coal. [Pg.187]

The dynamic viscosity is corrected to take in account the presence of fines at a volumetric concentration of 0.089. The dynamic viscosity of water is 1.2 cP, the Einstein-Thomas equation is applied ... [Pg.187]

In Chapter 1, the increase in dynamic viscosity due to the volumetric concentration of solids was discussed it can be expressed as the Einstein Thomas equation ... [Pg.209]

By the Einstein-Thomas equation, the dynamic viscosity of the carrier liquid needs to be corrected for a concentration of 0.0405 in the upper layer ... [Pg.214]

Self-diffusion coefficients are dynamic properties that can be easily obtained by molecular dynamics simulation. The properties are obtained from mean-square displacement by the Einstein equation ... [Pg.165]

Einstein studied homogeneous slurries of spherical panicles in a liquid of the same density. He showed that the distordon of the streamlines around the particles caused the dynamic viscosity of the slurry to increase according to the equation... [Pg.294]

Deser, S., Jackiw, R., and tHofft, G. (1984) Three-dimensional Einstein gravity dynamics of flat space. Annals of Physics. 152 220—35. (In three spacetime dimensions, the Einstein equations imply that source-free regions are flat.)... [Pg.214]

The final section (Section 5.8) introduces dynamic light scattering with a particular focus on determination of diffusion coefficients (self-diffusion as well as mutual diffusion), particle size (using the Stokes-Einstein equation for the diffusion coefficient), and size distribution. [Pg.196]

In dynamic light scattering (DLS), or photon correlation spectroscopy, temporal fluctuations of the intensity of scattered light are measured and this is related to the dynamics of the solution. In dilute micellar solutions, DLS provides the z-average of the translational diffusion coefficient. The hydrodynamic radius, Rh, of the scattering particles can then be obtained from the Stokes-Einstein equation (eqn 1.2).The intensity fraction as a function of apparent hydrodynamic radius is shown for a triblock solution in Fig. 3.4. The peak with the smaller value of apparent hydrodynamic radius, RH.aPP corresponds to molecules and that at large / Hs,Pp to micelles. [Pg.136]

The Fickian diffusion is based on the random walk and includes diffusion coefficient Dwhich is related to the dynamic cross-section of the molecule and the frictional losses it experiences as it moves through the medium. The semiempiri-cal Einstein equation (see (7.12)) relates the distance traveled by the molecule in the time interval to the diffusion coefficient. [Pg.351]

The paper is organized as follows in section 2, we briefly review the geometry and dynamics of the Universe and then give the Einstein-Friedman-Lemaitre (hereafter EEL) equations section 3 introduces some important quantities needed for observations in section 4, we rapidly present some solutions of the EEL equations, i.e. some cosmological models in section 5, the Standard Big Bang Nucleosynthesis Model is described while section 6 shows a statement of observations of primordial abundances in section 7, we confront the predictions of the Standard Big Bang Nucleosynthesis (hereafter SBBN) model to the observations of the primordial abundances a brief conclusion is... [Pg.1]


See other pages where Einstein dynamical equation is mentioned: [Pg.119]    [Pg.192]    [Pg.233]    [Pg.318]    [Pg.233]    [Pg.1257]    [Pg.46]    [Pg.202]    [Pg.188]    [Pg.298]    [Pg.106]    [Pg.443]    [Pg.444]    [Pg.294]    [Pg.226]    [Pg.177]    [Pg.294]    [Pg.94]    [Pg.133]    [Pg.40]    [Pg.421]    [Pg.34]    [Pg.52]    [Pg.115]    [Pg.169]    [Pg.42]   
See also in sourсe #XX -- [ Pg.6 , Pg.8 ]




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