hokhani's latest activity
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Hhokhani replied to the thread Undergrad Discrepancy in uncertainty among various operators.The uncertainty is given by: $$\langle (\Delta A)^2\rangle\langle (\Delta B)^2\rangle \ge \frac{1}{4} |\langle [A,B]\rangle|^2$$ with...
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Hhokhani posted the thread Undergrad Discrepancy in uncertainty among various operators in Quantum Physics.Consider a particle in an eigenstate of the Hamiltonian when the particle is in a 1D box with very large length ## L##. The operators...
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Hhokhani reacted to PeterDonis's post in the thread Graduate Time evolution of a detected particle with
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By no means. It could be bouncing back and forth within the confined space very fast. Or very slow. Or not at all. -
Hhokhani replied to the thread Graduate Time evolution of a detected particle.A lattice site is in fact an orbital and not a point, and the orbitals overlap to form band structure. So, the T.B Hamiltonian in...
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Hhokhani replied to the thread Undergrad Momentum measurement and uncertainty.To resolve this problem, Born-Von-Karman boundary conditions is used.
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Hhokhani replied to the thread Graduate Time evolution of a detected particle.If we had already the particle confined in a very narrow 1D box (to the extent of almost a point ##x_0##), then the speed of particle...
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Hhokhani replied to the thread Undergrad Momentum measurement and uncertainty.As a peculiar thing, suppose that we have constricted a particle in a 1D box with the length ##L##. By measurement of the momentum, the...
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Hhokhani replied to the thread Undergrad Momentum measurement and uncertainty.To approve further, the variance of wave functions changes by time and so the product of the two ##\Delta##s may change by time.
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Hhokhani reacted to PeterDonis's post in the thread Undergrad Momentum measurement and uncertainty with
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Mathematically, the uncertainty principle sets a lower limit on the product of the variance in position and the variance in momentum... -
Hhokhani reacted to PeterDonis's post in the thread Undergrad Momentum measurement and uncertainty with
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"Uncertainty" as in the uncertainty principle is not even about the variance of a large number of measurements of a single observable... -
Hhokhani replied to the thread Undergrad Momentum measurement and uncertainty.From theoretical point, in a single measurement, the wave function collapses on one of the momentum eigenstates, say ##|p_o\rangle##. Do...
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Hhokhani replied to the thread Undergrad Momentum measurement and uncertainty.I think this equation says that by a single measurement you would obtain the value of momentum in the interval ##\Delta p## around...
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HTheoretical measurement of momentum of a QM particle is equivalent to action of momentum operator on the particle wave function. What is...
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Hhokhani reacted to QuarkyMeson's post in the thread Graduate Time evolution of a detected particle with
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The Hamiltonian isn't something you measure, it's part of the specification of the system. Measuring energy is a separate operation... -
Hhokhani reacted to pines-demon's post in the thread Graduate Time evolution of a detected particle with
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Well (assuming free particle) starting at ##|\psi(t=0)\rangle=|x_0\rangle## you need only to carry $$|\psi(t)\rangle=e^{-i\hat H...