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Infinite volume limit

To investigate spontaneous symmetry breaking, one ordinarily has to start at finite volume and insert a source which explicitly breaks the symmetry. The source is removed only after the infinite volume limit is taken. We stress that the source does not have to be a quark mass (it could be a higher dimension operator), so one can investigate symmetry breaking even when the quark mass is exactly zero throughout the calculation. (To be precise, a quark mass does not explicitly violate vector symmetries, so it cannot play the role of the source in the thermodynamic limit needed here.)... [Pg.186]

This is the infinite-volume limit of the corresponding sum obtained from Eq. (5.43). [Pg.115]

This can be considered as an effective Hamiltonian, which describes the evolution of the observables that are relative to the region 2 of the infinite system Z . Notice we do not have, and do not need, any such thing for 2 -> Z" the thermodynamic limit (or rather the infinite volume limit) is already taken into account in With these preliminaries, the following results of interest are immediately proven ... [Pg.361]

The uniform electron gas for rg < 30 provides a nice example of the adiabatic connection discussed in Sect. 1.3.5. As the coupling constant A turns on from 0 to 1, the ground state wavefunction evolves continuously from the Kohn-Sham determinant of plane waves to the ground state of interacting electrons in the presence of the external potential, while the density remains fixed. (One should of course regard the infinite system as the infinite-volume limit of a finite chunk of uniform background neutralized by electrons.)... [Pg.32]

Let us point out an interesting open question on the infinite volume limit measure for [3 > (3c. The two point correlation function is... [Pg.64]

We consider both infinite volume limits and scaling limits, but in both cases we just give the basic ideas of the proofs. We will then focus on the dependence of the results on the boundary conditions. In reality, the only cases in which there is a dependence of the limit path measure on the boundary conditions is when w V ... [Pg.77]

The results of this section are taken from [Caravenna et al. (2005)] (scaling limits) and from [Caravenna et al. (2006b)] (infinite volume limits). [Pg.88]

Caravenna, F., Giacomin, G. and Zambotti, L. (2006b). Infinite Volume Limits of Polymer Chains with Periodic Charges, arXiv.org e-Print archive math.PR 0604426... [Pg.234]

Several boundary conditions have been used to prescribe the outer limit of an individual rhizosphere, (/ = / /,). For low root densities, it has been assumed that each rhizosphere extends over an infinite volume of. soil in the model //, is. set sufficiently large that the soil concentration at r, is never altered by the activity in the rhizosphere. The majority of models assume that the outer limit is approximated by a fixed value that is calculated as a function of the maximum root density found in the simulation, under the assumption that the roots are uniformly distributed in the soil volume. Each root can then extract nutrients only from this finite. soil cylinder. Hoffland (31) recognized that the outer limit would vary as more roots were formed within the simulated soil volume and periodically recalculated / /, from the current root density. This recalculation thus resulted in existing roots having a reduced //,. New roots were assumed to be formed in soil with an initial solute concentration equal to the average concentration present in the cylindrical shells stripped away from the existing roots. The effective boundary equation for all such assumptions is the same ... [Pg.337]

With these expansions, Eq. (259) gives, in the limit of an infinite volume,... [Pg.220]

For an ensemble of donor and acceptor molecules distributed at random in an infinite volume, it is easy to calculate the sum of the rate constants for transfer from donor to all acceptors because all donors of this ensemble are identical in the rapid diffusion limit ... [Pg.259]

A common feature of widely used apparatus like the paddle or basket method is their limited volume. Typical volumes used in these systems range from about 500 to 4000 mL, limiting their use for very poorly soluble substances. Theoretically at least, open systems may be operated with infinite volumes to complete the dissolution of even very poorly soluble com-... [Pg.24]

The problem is inherently a finite-size problem. Results that otherwise would be considered as finite-size effects and should be neglected are in this case essential. At the limit of infinite volume there will be no release at all. Bunde et al. [84] found a power law also for the case of trapping in a model with a trap in the middle of the system, i.e., a classical trapping problem. In such a case, which is different from the model examined here, it is meaningful to talk about finite-size effects. In contrast, release from the surface of an infinite medium is impossible. [Pg.78]

The range of the voidage change extends from that for the single particle in an infinite volume of fluid, e = 1, to the lower limit for the fixed bed, e0. At this point, Eq. (2.1) would still be valid, although it possesses a different physical meaning Instead of particles suspended by the fluid, this relation now signifies a fixed bed with pressure drop less than that required to balance the particles in the suspended state ... [Pg.218]

Note that excess properties are zero in the limit of infinite volume V, so that... [Pg.173]

Although in the semiclassical model the only dynamical variables are those of the molecule, and the extended Hilbert space. if = M M and the Floquet Hamiltonian K can be thought as only mathematically convenient techniques to analyze the dynamics, it was clear from the first work of Shirley [1] that the enlarged Hilbert space should be related to photons. This relation was made explicit by Bialynicki-Birula and co-workers [7,8] and completed in [9]. The construction starts with a quantized photon field in a cavity of finite volume in interaction with the molecule. The limit of infinite volume with constant photon density leads to the Floquet Hamiltonian, which describes the interaction of the molecule with a quantized laser field propagating in free space. The construction presented below is taken from Ref. 9, where further details and mathematical precisions can be found. [Pg.154]

The author became interested in the models of confinement of the hydrogen atom inside finite volumes [2,14,17,18] in connection with the measurements of the hyperfine structure of atomic hydrogen trapped in a-quartz [19,20]. Ten years later, he extended his interests to confinement in semi-infinite spaces limited by a paraboloid [21], a hyperboloid [9] and a cone [22] in connection with the exoelectron emission by compressed rocks [23,24], Jaskolski s report [1] cited several of the above-mentioned works [9,14,17, 18,21], each one of which had formulated and constructed exact solutions for new types of confinement for the hydrogen atom. This subsection is focussed on his citation of our article [9] ... [Pg.86]

In the CAM assay, the concentrations are in a dynamic state, i.e. they are not in a steady state. They ultimately dilute into an infinite volume. But the simple model can be expected to give at least semi-quantitative guidance for the early events, where the active volume is limited by the diffusion distance. [Pg.29]

In liquids, predictive methods for diffusivity are typically semiempirical, relating the diffusivity of a solute at infinite dilution to the solvent viscosity, the molar volumes of the components, and sometimes other quantities [15]. For finite concentrations, the manner in which the diffusion coefficients pass from one infinite-dilution limit to the other is sometimes complex, and the models that exist [15] typically have a parameter that must be fitted to data. [Pg.17]

The proportion of fluid elements experiencing a particular anomalous value of the Lyapunov exponent A / A°° decreases in time as exp(—G(X)t). In the infinite-time limit, in agreement with the Os-eledec theorem, they are limited to regions of zero measure that occupy zero volume (or area in two dimensions), but with a complicated geometrical structure of fractal character, to which one can associate a non-integer fractional dimension. Despite their rarity, we will see that the presence of these sets of untypical Lyapunov exponents may have consequences on measurable quantities. Thus we proceed to provide some characterization for their geometry. [Pg.56]

V r, V, z r, V- 6 Tl. V, z Tl, V, z T1,0, V 0 0 0,1 0, oo OQ 1,0 1, OO 1,2 1,2,3 12 ID constant volume condition cylindrical coordinates spherical coordinates elliptical cylinder coordinates bicylinder coordinates oblate and spheroidal coordinates zero thickness limit based on centroid temperature zeroeth order, first order value on the surface and at infinity infinite thickness limit first eigenvalue value at zero Biot number limit first eigenvalue value at infinite Biot number limit solids 1 and 2 surfaces 1 and 2 cuboid side dimensions net radiative transfer one-dimensional conduction... [Pg.195]

Here the partial molar volume is evaluated in the infinite-dilution limit with solvent-free mole fractions held fixed. [Pg.435]

The K-B theory expresses the thermodynamic quantities such as the partial molar volume and the isothermal compressibility for a solution in terms of the pair correlation functions of constituent molecular species. The expressions in terms of the site-site pair correlation functions are obtained by coupling the K-B theory with the RISM theory. When we consider a two-component system (a solute with m-sites and a solvent with n-sites) and the infinite dilution limit, the partial molar volume of the solute Vm and the isothermal compressibility kt can be expressed as, respectively. [Pg.148]


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