Abstract
The development of time-dependent perturbation theory was initiated by Paul Dirac’s early work on the semi-classical description of atoms interacting with electromagnetic fields
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
P.A.M. Dirac, Proc. Roy. Soc. London A 112, 661 (1926).
- 2.
F.J. Dyson, Phys. Rev. 75, 1736 (1949).
- 3.
The transformation law for operators from the Schrödinger picture into the interaction picture implies H D (t) ≡ V D (t). The notation V D (t) is therefore also often used for H D (t).
- 4.
If the perturbation V (t) contains directional information (e.g. polarization of an incoming photon or the direction of an electric field), then we might also like to calculate probabilities for the direction of dissociation of the hydrogen atom. This direction would be given by the k vector of relative motion between the electron and the proton after separation. For the calculation of directional information we would have to combine the spherical Coulomb waves | k, ℓ, m⟩ into states which approximate plane wave states | k⟩ at infinity, similar to the construction of incoming approximate plane wave states in Section \e13.5, see also the discussion of the photoeffect in [2].
- 5.
Recall that the notation tacitly implies dependence of the operators V and W on x and p (just like we usually write H instead of H(x, p) for a Hamilton operator).
- 6.
G. Wentzel, Z. Phys. 43, 524 (1927).
- 7.
J.R. Oppenheimer, Z. Phys. 55, 725 (1929).
- 8.
W. Wessel, Annalen Phys. 397, 611 (1930); E.C.G. Stückelberg & P.M. Morse, Phys. Rev. 36, 16 (1930); M. Stobbe, Annalen Phys. 399, 661 (1930).
- 9.
Alternatively, we could have used box normalization for the incoming plane waves, \(\langle x\vert k\rangle =\exp (\mathrm{i}k \cdot x)/\sqrt{V}\) both in dw k → k′ and in j ( ⇒ j = ℏk ∕ (mV ) = v ∕ V ), or we could have rescaled both dw k → k′ and j with the conversion factor 8π3 ∕ V to make both quantities separately dimensionally correct, [dw k → k′ ] = s − 1, [j] = cm − 2s − 1. All three methods yield the same dimensionally correct result for the scattering cross section, of course.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
Copyright information
© 2012 Springer Science+Business Media, LLC
About this chapter
Cite this chapter
Dick, R. (2012). Time-dependent Perturbations in Quantum Mechanics. In: Advanced Quantum Mechanics. Graduate Texts in Physics. Springer, New York, NY. https://doi.org/10.1007/978-1-4419-8077-9_13
Download citation
DOI: https://doi.org/10.1007/978-1-4419-8077-9_13
Published:
Publisher Name: Springer, New York, NY
Print ISBN: 978-1-4419-8076-2
Online ISBN: 978-1-4419-8077-9
eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)