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Heisenberg relationship

When the mass m of an object is relatively large, as is true in daily life, then both Ax and Av in the Heisenberg relationship can be very small. We therefore have no apparent problem in measuring both position and velocity for visible objects. The problem arises only on the atomic scale. Worked Example 5.6 gives a sample calculation. [Pg.172]

The Heisenberg relationship says that the uncertainty in an object s position, Ax, times the uncertainty in its momentum, Amv, is equal to or greater than the quantity h/4ir. [Pg.172]

Fuzzy set methods have been developed for a variety of applications, initially mostly in engineering and technology. However, many applications in the natural sciences quickly followed. " The Heisenberg relationship and many other aspects of quantum mechanics can be interpreted in terms of fuzzy sets. " A straightforward extension of these ideas to some of the elementary concepts of chemistry suggests the following rather... [Pg.139]

Figure 3.1. Simplified mechanistic pattern of simultaneous TPA ((a) and (b)) in comparison with stepwise excitation (c) with two photons (< i and co2 — excitation frequencies, t = lifetime of the state considered, dashed line = energy distribution of the virtual state according to the Heisenberg relationship, solid line = energy levels of the real states, i.e., the ground state and the excited states, r> = absorption cross section from ground state to the virtual state, Ojf = absorption cross section from the virtual state to the final excited state), (a) Simultaneous excitation with one color, o> = Figure 3.1. Simplified mechanistic pattern of simultaneous TPA ((a) and (b)) in comparison with stepwise excitation (c) with two photons (< i and co2 — excitation frequencies, t = lifetime of the state considered, dashed line = energy distribution of the virtual state according to the Heisenberg relationship, solid line = energy levels of the real states, i.e., the ground state and the excited states, r> = absorption cross section from ground state to the virtual state, Ojf = absorption cross section from the virtual state to the final excited state), (a) Simultaneous excitation with one color, o> = <a2- (b) Simultaneous excitation with two colors, coi t co2. (c) Stepwise excitation with two photons in which the first excited state operates as an intermediate state.
TP excitation requires at least one virtual state. The latter is not a physically observable state. The lifetime x, is set to several femtoseconds. Lifetime broadening of the virtual state can be approximated by the Heisenberg relationship, Eq. (1) ... [Pg.118]

The conditions for such a nuclear resonance absorption are very stringent. Using the Heisenberg relationship (4.66) we can estimate the half-value width of the 129 keV peak to be 5 X 10 eV. We can also use relation (4.34) to calculate the iridium atom recoil energy to be 46 X 10 eV. Thus the 7-my leaves the source with an energy of (129 x 10 ... [Pg.154]

Quantum mechanical principles. Fundamental constants of the universe the speed of light, die Boltzmann constant, the Planck constant. The wave-particle duality. The link between the Microscopic World of Energetic of Atoms/Molecules and the Macroscopic World de Broglie relationship, the Heisenberg relationships, and statistical distributions. The Bohr interpretation of the hydrogen atom. The postulates of quantum in the wave funetion. [Pg.3]

This result confirms the quantum behavior of the quantum motion that is not entirely encompassed by the (semi) classical turning points domain, even its major part lays there, with the rest being dispersed by tunneling process (see the Postulate I discussion), being however a new manifestation of the indeterminacy (Heisenberg) relationship that impedes the position and momentum to be with the same precision simultaneously determined. Further aspects of the quantum vibrational motions are to be discussed in the next sections and chapter of this volume, whereas the application to various molecular systems will be systematically presented in the Volume 3 of this five-volume set. [Pg.209]

For quasi-stable nuclides, the measured width, F, of the resonance is given. To estimate the approximate half-life, the Heisenberg relationship may be used, the half-life = 4.56 x 10 seconds / F (MeV). The effective literature cutoff date for data in this edition of the table is December 2010. [Pg.1896]

With these quantities, the predicted lifetime of corresponding bondons, obtained from the working expressions for bondonic mass and velocity working through the basic time-energy Heisenberg relationship, is here restrained at the level of kinetic energy only for the bondonic particle thus, one yields the subsequent analytical forms ... [Pg.23]

The spectrum of the femtosecond pulse provides some infonnation on whether the input pulse is chirped, however, causing the temporal width of I(t) to be broader than expected from the Heisenberg indetenninancy relationship. [Pg.1975]

This relationship is known as the Heisenberg uncertainty principle. [Pg.21]

Ultrafast time-resolved resonance Raman (TR ) spectroscopy experiments need to consider the relationship of the laser pulse bandwidth to its temporal pulse width since the bandwidth of the laser should not be broader than the bandwidth of the Raman bands of interest. The change in energy versus the change in time Heisenberg uncertainty principle relationship can be applied to ultrafast laser pulses and the relationship between the spectral and temporal widths of ultrafast transform-limited Gaussian laser pulse can be expressed as... [Pg.132]

A large number of mathematical formulas will be found in the book. This may be regarded as a disadvantage particularly because some of them are not readily to apply in daily analytical practice. However, great scientists, explicitly Emanuel Kant, said that a scientific branch contains only so much of science as it applies mathematics. Consequently, all the relationships which can be described mathematically should be so described. It is true despite Werner Heisenbergs statement Although natural processes can be described by means of simple laws which can be precisely formulated, these laws, on the other hand, cannot directly be applied to actions in practice. [Pg.5]

The laser used to generate the pump and probe pulses must have appropriate characteristics in both the time and the frequency domains as well as suitable pulse power and repetition rates. The time and frequency domains are related through the Fourier transform relationship that hmits the shortness of the laser pulse time duration and the spectral resolution in reciprocal centimeters. The limitation has its basis in the Heisenberg uncertainty principle. The shorter pulse that has better time resolution has a broader band of wavelengths associated with it, and therefore a poorer spectral resolution. For a 1-ps, sech -shaped pulse, the minimum spectral width is 10.5 cm. The pulse width cannot be <10 ps for a spectral resolution of 1 cm . An optimal choice of time duration and spectral bandwidth are 3.2 ps and 3.5 cm. The pump pulse typically is in the UV region. The probe pulse may also be in the UV region if the signal/noise enhancements of resonance Raman... [Pg.881]

Incidentally, the uncertainty principle associated with the name of Heisenberg, well known in quantum mechanics, follows from the expression given here when de Broglie s relationship connecting the momentum of a particle with its wavelength is included. [Pg.268]

While for some purposes it may be necessary to have accurate frequency definition, for others good time discrimination is useful. These are opposite requirements. Because of the Fourier relationship between frequency and time, the more precisely the time of a signal is known, the greater bandwidth of frequencies is necessary (there is a close analogy here with Heisenberg s uncertainty principle). Approximately, the time resolution t is the reciprocal of the bandwidth Bw, so that their product Bwr 1. [Pg.70]

Equations 2.85 and 2.86 may be considered the Schrodinger representation of the absorption of radiation by quantum systems in terms of spectroscopic transitions between states i) and /). In the Schrodinger picture, the time evolution of a system is described as a change of the state of the system, as implemented here in the form of the time-dependent perturbation theory. The results hardly resemble the classical relationships outlined above, compare Eqs. 2.68 and 2.86, even if we rewrite Eq. 2.86 in terms of an emission profile. Alternatively, one may choose to describe the time evolution in terms of time-dependent observables, the Heisenberg picture . In that case, expressions result that have great similarity with the classical expressions quoted above as we will see next. [Pg.51]

This relationship, known as Bloch s rule, applies in the localized-electron limit where the interatomic spin-spin interaction is described by the superexchange perturbation theory of eq. (23) with 7n J J is the Heisenberg exchange energy. Calculations by Shrivastava and... [Pg.279]

The natural line width is determined by Heisenberg s uncertainty relationship ... [Pg.52]

In Table 11 are compiled the results concerning 2-D Heisenberg systems a is the anisotropy coefficient and the perpendicular susceptibility is calculated from the relationship ... [Pg.139]

The symbol ([A,B]) is just (T [A,B] T, a quantum-mechanical average over the quantum state Tq. The inequality is known as Heisenberg-Kennard-Robertson relationship, which has often been interpreted as the mathematical expression of the disturbance following measurement. Ballentine noted that this relationship does not seem to have any bearing on the issue of joint measurement instead, this relation can be traced back to the preparation process of an initial state, see Ref. [1,10]. [Pg.58]

The imprecise nature of Schrodinger s model was supported shortly afterwards by a principle proposed by Werner Heisenberg, in 1927. Heisenberg demonstrated that it is impossible to know both an electron s pathway and its exact location. Heisenberg s uncertainty principle is a mathematical relationship that shows that you can never know both the position and the momentum of an object beyond a certain measure of precision. [Pg.657]


See other pages where Heisenberg relationship is mentioned: [Pg.1796]    [Pg.1742]    [Pg.50]    [Pg.1641]    [Pg.1742]    [Pg.1796]    [Pg.1742]    [Pg.50]    [Pg.1641]    [Pg.1742]    [Pg.40]    [Pg.15]    [Pg.57]    [Pg.251]    [Pg.528]    [Pg.3]    [Pg.361]    [Pg.3]    [Pg.406]    [Pg.128]    [Pg.254]    [Pg.126]    [Pg.222]    [Pg.104]    [Pg.122]    [Pg.2]    [Pg.83]    [Pg.351]   
See also in sourсe #XX -- [ Pg.118 ]




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