ØKey Theorem:
Ø For large enough mass, the lowest
energy eigenfunction is localised to the global min. of the
potential
ØSolutions of Schrödinger for general Vfull are
intractable
ØApproximate solutions for polynomial Vfull
lExpand potential as Vfull=Vsimple+Vperturb
lUsing completeness, expand
eigenfunctions in terms of those of Vsimple
l
lTo approximate lowest energy
eigenstate, choose ai to minimise energy
expectation
l
l
l
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l
Ø