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Graduate Problem Map

Graduate problems should make assumptions explicit. They should ask not only for an answer, but for the conditions under which the answer is meaningful.

Stage Problem Family Canonical Page Graduate Emphasis
1 Toolkit readiness Diagnostic Checklist domains, spectra, distributions, convergence
2 Formalism review Exercises and Problems projectors, mixed states, commutators, postulates
3 Approximation methods Anharmonic Oscillator Perturbation expansion parameter and matrix elements
4 Scattering Gaussian Potential Born normalization convention and validity of Born approximation
5 Semiclassical reasoning WKB Barrier Tunneling turning points and exponential estimates
6 Composite systems Partial Trace Exercises local statistics and entanglement diagnostics
7 Identical particles and Fock space Identical-Particle Exercises and Fock-Space Exercises exchange, occupation numbers, second-quantized notation
8 Numerical validation Benchmark Problems convergence and error interpretation
ID Problem Type Required Assumption
QM-PROB-G101 Prove or apply a commutator identity operator domains or finite-dimensional setting
QM-PROB-G201 Use degenerate perturbation theory chosen degenerate subspace and perturbation order
QM-PROB-G301 Evaluate a Born amplitude weak, short-range potential and normalization convention
QM-PROB-G401 Estimate WKB tunneling slowly varying barrier away from turning points
QM-PROB-G501 Compute a reduced density operator tensor-factor ordering and subsystem definition
QM-PROB-G601 Validate a numerical eigenvalue calculation refinement variable and reference result

A graduate solution should state:

  • the Hilbert space and domain assumptions;
  • the normalization convention;
  • whether the spectrum is discrete, continuous, or mixed;
  • the approximation parameter and retained order;
  • the role of symmetry or degeneracy;
  • the physical observable extracted from the calculation;
  • at least one limiting case or benchmark.
  • Treating a perturbative result as exact because the first correction is compact.
  • Treating a finite-dimensional example as proof of an infinite-dimensional domain-sensitive statement.
  • Calling a numerical plot evidence without a convergence study.
  • Treating an effective model as fundamental without stating its regime.
  • R. Shankar, Principles of Quantum Mechanics, 2nd ed., Springer, 1994.
  • J. J. Sakurai and J. Napolitano, Modern Quantum Mechanics, 3rd ed., Cambridge University Press, 2020.
  • C. Cohen-Tannoudji, B. Diu, and F. Laloe, Quantum Mechanics, Wiley, 1977.
  • M. Reed and B. Simon, Methods of Modern Mathematical Physics I: Functional Analysis, Academic Press, 1980.