Skript / lecture notes - Universität Paderborn

Prof. Dr. Wolf Gero Schmidt
Universität Paderborn, Lehrstuhl für Theoretische Physik
Bemerkungen remarks
w lm = 2π
2 |A ml| 2 δ(ω ml − ω) (1.81)
”Fermi’s Goldene Regel” ”Fermi’s golden rule”
– Energieerhaltung durch δ–Funktion δ function ensures energy conservation
– Übergangsrate ∼ |Übergangsmatrixelement| 2 transition rate ∼ |matrix
element| 2 of the perturbation between the final and initial states
– Although named after Fermi, most of the work leading to the Golden Rule
was done by Dirac, who formulated an almost identical equation, including
the three components of a constant, the matrix element of the perturbation
and an energy difference. It is given its name because, being such a useful
relation, Fermi himself called it ”Golden Rule”.
1.3 Das Wasserstoffmolekülion
The hydrogen molecule ion
Einfachste chemische Verbindung H 2
+ The hydrogen molecule ion consists of an electron
orbiting about two protons, and is the simplest imaginable molecule. Let us investigate
whether or not this molecule possesses a bound state: i.e., whether or not it possesses a
ground-state whose energy is less than that of a hydrogen atom and a free proton.
e -
+
A
x
+
B
R A
RB
Potentialschema schematic potential
V
R A
R B
x
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