Recent content by osturk

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    Relation between commutation and quantization

    Exactly.. I want to know if the notion that I've got, that commutation and quantization is fundamentally related to each other, is true or not. If it is true; then, is there a mathematical way to show that in a more general way than the example that I gave above.
  2. O

    Relation between commutation and quantization

    relation between "commutation" and "quantization" Hi people; Over the several texts I have read, I got the impression that position-momentum commutation relations is the cause of "quantization" of the system. Or, they are somehow fundamentally related. The only relation I know of, is to...
  3. O

    Excitation by photons smaller than energy interval

    thanks for the answer. I only have the 1st volume of Messiah's book, and a google search on the issue returns nothing, so.. But, the total energy of the system seems to be increased already.. initially we have a photon with \hbar\omega, and then, a system with energy \hbar\omega_{0}, but no...
  4. O

    Excitation by photons smaller than energy interval

    Hi people, Time-dependent perturbation theory allows for transitions to excited states, through a sinusoidal perturbation whose frequency is smaller than the energy difference between the states. (That is, P_{a \rightarrow b}=\frac{sin^{2}[(\omega_{0}-\omega)t/2]}{(\omega_{0}-\omega)^2}...
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    Relativistic doppler effect - inconsistency in my derivations

    Hello everyone, I'm trying to calculate the doppler shift in frequency of a moving source. I'm approaching the problem from two different frames of reference and getting inconsistent results. what am I missing here? consider the special case of transverse doppler effect (θ=π/2). light...
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    Wavefunction collapse on degenerate states

    Hello, I am a beginner on the sbject so please correct if I'm using some sloppy terminology. I'll try to be clear. Consider a Hamiltonian with degenerate energy eigenstates (say the degeneracy is on angular momentum as in hydrogen atom). Which of the degenerate eigenstates would the wave...
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    Schrodinger Equation in momentum space? ?

    ah, yes, it is true in momentum space. I missed that.
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    Schrodinger Equation in momentum space? ?

    Hello. I had the QM course this year, so I'll try to help: this is not actually true. We can not substitute operators with scalars, in general. An operator, operates on a function, and yields another function which is, in general, different than the initial function. However, if an operator...
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    Setting up Fick's Law with Internal heating

    john, the last term in heat conduction equation should be J^2*rho. This is the general form for the local heat production (and you don't need the derivatives). J is the current density (charge per time per area), and rho is the resitivity (resistance*length). However, if the cross section and...
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    Under free vibration does it vibrate in all the modes

    When hit by a random impulse, a mechanical system will vibrate in all modes, but in different amplitudes.. Amplitudes for each mode, Ai, will depend on the displacements of the structure right after the impulse. Here, an impulse is defined as an instantaneous relief from a deformed state...
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    Discover the Best Way to Cool Your Coffee in Just 5 Minutes: Milk vs. No Milk

    this was fun. let; Tm = temperature of the milk, Tr = temperature of the room, T(t) = temperature of the coffee, w/o the milk T'(t) = temperature of the coffee, w/ the milk T0 = initial temp of the coffee (HOT!) K: a constant between 0 and 1 depending on the ratio of mass of the milk...
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