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Complex symmetric interactions

The characteristics developed here emanate from the so-called complex scaling method [11] of atomic and molecular physics [14, 15], The observance to incorporate complex symmetric interactions in effect provides for transitions from specific quantum non-local representations to classical locality. [Pg.75]

It is also straightforward to generalize the off-diagonal interaction to incorporate the previously mentioned resonance picture of unstable states by using a complex symmetric operator. For general discussions on this issue, we refer to the proceedings of the Uppsala-, Lertorpet- and the Nobel-Satellite workshops and references therein [13-15]. Thus one may arrive at a complex symmetric secular problem (note that the same matrix construction may be derived from a suitable hermitean matrix in combination with a nonpositive definite metric [9] see also below), which surprisingly leads to a comparable secular equation as the one obtained from Eq. (1). To be more specific we write... [Pg.118]

In summary, the model allows for two types of interactions between the mirror spaces, the weak kinematical perturbation and the adiabatic and sudden limits equivalent to Eq. (17) or Eqs. (29)-(34). The overwhelming rate of particles over antiparticles in the Universe is inferred in this picture once the particular particle state has been selected. The Minkowski metric of the special theory of relativity is represented here by a non-positive definite metric, Eq. (8), bringing about a quantum model with a complex symmetric ansatz. Although the latter permits general symmetry violations, it is nevertheless surprising that fundamental transformations between complex symmetric representations and canonical forms come out unitary. [Pg.131]

The simplest example of a complex symmetric operator is the non-relativistic many-particle Hamiltonian H for an atomic, molecular, or solid-state system, which consists essentially of the kinetic energy of the particles and their mutual Coulomb interaction. Since such a Hamiltonian is both self-adjoint and real, one obtains... [Pg.95]

Spectra of samples in the liquid state (Fig. 2.6-lB) are given by molecules which may have any orientation with respect to the beam of the spectrometer. Like in gases, flexible molecules in a liquid may assume any of the possible conformations. Some bands are broad, since they are the sum of spectra due to different complexes of interacting molecules. In the low frequency region spectra often show wings due to hindered translational and rotational motions of randomly oriented molecules in associates. These are analogous to the lattice vibrations in molecular crystals, which, however, give rise to sharp and well-defined bands. The depolarization ratio p of a Raman spectrum of molecules in the liquid state (Eqs. 2.4-11... 13) characterizes the symmetry of the vibrations, i.e., it allows to differ between totally symmetric and all other vibrations (see Sec. 2.7.3.4). [Pg.37]

It is actually a straightforward procedure to include gravitational interactions within the present framework. Although gravity is associated with a tensor field, we will here initiate the formulation by augmenting the present complex symmetric model, in the basis m, m), with the scalar interaction (the word scalar is placed in quotation marks since the potential will be built into an appropriate matrix formalism, see also a more detailed formulation in the next section) ... [Pg.77]

As discussed earlier, the present interpretation of the truth table can be obtained from conventional representations with the use of a non-positive definite metric A All = —A22=1 Ai2=Ai2=0. In this picture, we can use conventional brake nomenclature, while for another selection of A, leading e.g. to a complex symmetric choice, it would require complex symmetric realisations. In both cases, the formulation is biorthogonal. With this realisation, we can make an identification between Eqs. (1.63) and (1.66), making the replacement q = /c(r), where q is related to the probability function/operator of the simple proposition Q = P. Hence, we realise a probabilistic origin combined with the nonclassical, self-referential character of gravitational interactions. Note also the analogy between the formulations, i.e. that the result of a classical measurement, i.e. the truth or... [Pg.20]

In conclusion, we emphasise the following points (i) we have re-derived a previously obtained operator array formulation, which in its complex symmetric form permits a viable map of gravitational interactions within a combined quantum-classical structure (ii) the choice of representation allows the implementation of a global superposition principle valid both in the classical as well as the quantum domain (iii) the scope of the presentation has focused on obtaining well-known results of Einstein s theory of general relativity particularly in connection with the correct determination of the perihelion motion of the planet Mercury (iv) finally, we have obtained a surprising relation with Godel s celebrated incompleteness theorem. [Pg.21]

A telltale sign of ICEP is the presence of non-uniform ICEO flow around the particle, which leads to complex hydrodynamic interactions with other particles and walls. For example, the basic quadrupolar flow in Fig. la causes two symmetric particles to move toward each other along the field axis and then push apart in the normal direction [13, 15]. A finite cloud of such particles would thus become squashed into a disk-like spreading pancake perpendicular to the field axis [3]. The same flow field can also cause particles to be repelled from insulating walls (perpendicular to the field) [16] or attracted toward electrodes (normal to the field), but these are only guiding principles. Broken symmetries in particle shape or wall geometry, however, can cause different motion due to combined effects of DEP and ICEP, even opposite to these principles, and the interactions of multiple particles can also be influenced strongly by walls. Such effects have not yet been fully explored in experiments or simulations. [Pg.527]

A cyclopentadienyl nickel complex featuring a rare Si-Ni linkage has been prepared by reacting SiGp 2 with Ni(Gl)Gp(PPh3) the solution spectra and solid-state studies have identified the product as [GpNi /i r7 (Ni),77 (Si)-(Gp -Si(Gl)(77 -Gp )], 113. The solid-state structure of 113 shows an Ni-Si bond length of 220 pm and a fairly symmetrical interaction between Ni and the rf-Cp (ca. 204 pm). [Pg.165]

Figure 17.12 Ribbon diagram of EMPl bound to the extracellular domain of the erythropoietin receptor (EBP). Binding of EMPl causes dimerization of erythropoietin receptor. The x-ray crystal structure of the EMPl-EBP complex shows a nearly symmetrical dimer complex in which both peptide monomers interact with both copies of EBP. Recognition between the EMPl peptides and EBP utilizes more than 60% of the EMPl surface and four of six loops in the erythropoietin-binding pocket of EBP. Figure 17.12 Ribbon diagram of EMPl bound to the extracellular domain of the erythropoietin receptor (EBP). Binding of EMPl causes dimerization of erythropoietin receptor. The x-ray crystal structure of the EMPl-EBP complex shows a nearly symmetrical dimer complex in which both peptide monomers interact with both copies of EBP. Recognition between the EMPl peptides and EBP utilizes more than 60% of the EMPl surface and four of six loops in the erythropoietin-binding pocket of EBP.
To conclude, the introduction of species-selective membranes into the simulation box results in the osmotic equilibrium between a part of the system containing the products of association and a part in which only a one-component Lennard-Jones fluid is present. The density of the fluid in the nonreactive part of the system is lower than in the reactive part, at osmotic equilibrium. This makes the calculations of the chemical potential efficient. The quahty of the results is similar to those from the grand canonical Monte Carlo simulation. The method is neither restricted to dimerization nor to spherically symmetric associative interactions. Even in the presence of higher-order complexes in large amounts, the proposed approach remains successful. [Pg.237]

Complex [(CXI )Ir(/j,-pz)(/i,-SBu )(/j,-Ph2PCH2PPh2)Ir(CO)] reacts with iodine to form 202 (X = I) as the typical iridium(II)-iridium(II) symmetrical species [90ICA(178)179]. The terminal iodide ligands can be readily displaced in reactions with silversalts. Thus, 202 (X = I), upon reaction with silver nitrate, produces 202 (X = ONO2). Complex [(OC)Ir(/i,-pz )(/z-SBu )(/i-Ph2PCH2PPh2)Ir(CO)] reacts with mercury dichloride to form 203, traditionally interpreted as the product of oxidative addition to one iridium atom and simultaneous Lewis acid-base interaction with the other. The rhodium /i-pyrazolato derivative is prepared in a similar way. Unexpectedly, the iridium /z-pyrazolato analog in similar conditions produces mercury(I) chloride and forms the dinuclear complex 204. [Pg.208]

In a regime of strong interaction between the chains no optical coupling between the ground slate and the lowest excited state occurs. The absence of coupling, however, has a different origin. Indeed, below 7 A, the LCAO coefficients start to delocalize over the two chains and the wavefunclions become entirely symmetric below 5 A due to an efficient exchange of electrons between the chains. This delocalization of the wavcfunclion is not taken into account in the molecular exciton model, which therefore becomes unreliable at short chain separations. Analysis of the one-electron structure of the complexes indicates that the... [Pg.375]

The potential energy is often described in terms of an oscillating function like the one shown in Figure 10.9(a) where the minima correspond to the relative orientations in which the interactions are most favorable, and the maxima correspond to unfavorable orientations. In ethane, the minima would occur at the staggered conformation and the maxima at the eclipsed conformation. In symmetrical molecules like ethane, the potential function reflects the symmetry and has a number of equivalent maxima and minima. In less symmetric molecules, the function may be more complex and show a number of minima of various depths and maxima of various heights. For our purposes, we will consider only molecules with symmetric potential functions and designate the number of minima in a complete rotation as r. For molecules like ethane and H3C-CCI3, r = 3. [Pg.564]


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See also in sourсe #XX -- [ Pg.115 ]




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