Quantum Chemistry
On the first day of Christmas, my professor gave to me: An exam in Quantum Chemistry.
On the second day of Christmas, my professor gave to me: a double integral and an exam in Quantum Chemistry.
On the third day of Christmas, my professor gave to me: three orbitals, a double integral, and an exam in Quantum Chemistry.
On the fourth day of Christmas, my professor gave to me: four harmonic oscillators, three orbitals, etc.
On the fifth day of Christmas, my professor gave to me: Five Hermitian Operators! Four harmonic ocillators, three orbitals, etc.
On the sixth day of Christmas, my professor gave to me: six spin-orbit couplings, etc.
On the seventh day of Christmas, my professor gave to me: seven basis functions, etc.
On the eighth day of Christmas, my professor gave to me: eight time dependent perturbations, etc.
On the ninth day of Christmas, my professor gave to me: nine Slater determinants, etc.
On the tenth day of Christmas, my professor gave to me: ten electrons tunneling, etc.
On the eleventh day of Christmas, my professor gave to me: eleven photons emitting, etc.
On the twelfth day of Christmas, my professor gave to me: 12 fermions exchanging, etc.