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Action quantum

Here, h = (6.626 068 76 0.000 000 52)-10 34 Js is the Planck constant, also known as Planck s action quantum v is the frequency of the photons. Quantum theory is required to calculate the spectral distribution of the energy emitted by a body. Other aspects of heat transfer can, in contrast, be covered by classical theory, according to which the radiation is described as the emission and propagation of electromagnetic waves. [Pg.504]

This expression relates the action-at-a-distance forces between atoms to the macroscopic deformations and dominated adhesion theoiy for the next several decades. The advent of quantum mechanics allowed the interatomic interactions giving rise to particle adhesion to be understood in greater depth. [Pg.147]

Wirkungs-losigkeit, /. inactivity, ineffectiveness, inefficiency, -moglichkeit, /. possible effect, -quant, -quantum, n. quantum of action, effective quantum, -querschnitt, m. effective cross section, -sphkre, /. sphere of action, -variabel, n. action variable, -ver mSgen, n. power of action, working power. [Pg.516]

In Lee s discrete quantum mechanics, the classical action Sc is again replaced by the discrete action (equation 12,33), and, because both x and t are variables, the continuous path [ Dcx t)] is replaced by the discrete path [Dox t)] j] d x ndtji, where is the same as for the continuous case. The parameter n... [Pg.657]

Benioff introduced a series of Hamiltonians describing the evolution of a system consisting of spin-1/2 particles (spins up/down corresponding to binary logical states 0/1) occupying the sites of a lattice. The initial. state of the system I (t = 0) corresponds to the input state of a computation. Benioff s systems evolve, under the action of a Hamiltonian, in such a way that the quantum states (0),... [Pg.674]

PM spectra and their decays in DOO-PPV films and dilute solutions, we conclude that the primary excitations in DOO-PPV films are also singlet excitons [26]. The long excitonic lifetime and a corresponding high PL quantum efficiency [27] indicates that DOO-PPV is a high quality polymer material, which is very suitable for electrooptics and laser action applications [28],... [Pg.116]

Ward, W. W., and Seliger, H. H. (1976). Action spectrum and quantum yield for the photoinactvation of mnemiopsin, a bioluminescent photoprotein from the ctenophore Mnemiopsis sp. Photochem. Photobiol. 23 351-363. [Pg.450]

The form of the action principle given above was first applied to quantum mechanics to describe the time evolution of pure states (i.e. [Pg.223]

Section II discusses the real wave packet propagation method we have found useful for the description of several three- and four-atom problems. As with many other wave packet or time-dependent quantum mechanical methods, as well as iterative diagonalization procedures for time-independent problems, repeated actions of a Hamiltonian matrix on a vector represent the major computational bottleneck of the method. Section III discusses relevant issues concerning the efficient numerical representation of the wave packet and the action of the Hamiltonian matrix on a vector in four-atom dynamics problems. Similar considerations apply to problems with fewer or more atoms. Problems involving four or more atoms can be computationally very taxing. Modern (parallel) computer architectures can be exploited to reduce the physical time to solution and Section IV discusses some parallel algorithms we have developed. Section V presents our concluding remarks. [Pg.2]

It is now shown how the abrupt changes in the eigenvalue distribution around the central critical point relate to changes in the classical mechanics, bearing in mind that the analog of quantization in classical mechanics is a transformation of the Hamiltonian from a representation in the variables pR, p, R, 0) to one in angle-action variables (/, /e, Qr, 0) such that the transformed Hamiltonian depends only on the actions 1r, /e) [37]. Hamilton s equations diR/dt = (0///00 j), etc.) then show that the actions are constants of the motion, which are related to the quantum numbers by the Bohr correspondence principle [23]. In the present case,... [Pg.46]

At this stage the argument only explains changes in the hnes of constant bent quantum number vt (corresponding to the action 7 ) in Fig. la. The... [Pg.47]


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