Nonlocal phenomenon

Once an approximate XC functional has been selected, the need to solve the KS equations remains. Several strategies have emerged, which differ mainly in two ways the type of basis in which the KS orbitals are expanded and the manner in which the electrostatic component the KS equations is handled. The large number feasible DFT approaches is in sharp contrast to the more familiar HF formalism where the linear combination Gaussian-type orbitals (LCGTO) approach clearly dominates. The wide variation in DFT schemes is a direct result of the foct that exchange is no longer a nonlocal phenomenon as... 

As we have emphasized aheady, the study of plasticity is one of the centerpieces of the mechanics of materials. A wide array of technologies depend upon the ability to deform materials into particular desirable shapes, while from a scientific perspective I personally find the subject of great interest because it is an intrinsically dissipative process featuring history dependence and is a strong function of the material s microstructure. In addition, from the effective theory perspective, the study of plasticity is built around the motion and entanglement of dislocations which requires the construction of theories of lines and their interaction thus ushering in a certain nonlocality to the phenomenon right from the outset. 

Hence, nonlocality and spatial dispersion are two expressions for one and the same physical phenomenon. " ... 

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