Jabarkan keterangan: dari Mekanika kuantum

adalah tetapan Planck,  (Js), dan

adalah frekuensi dari cahaya (Hz)

Dalam spektrometer massa, telah dibuktikan bahwa garis-garis spektrum dari atom yang di-ionisasi tidak kontinu, hanya pada frekuensi/panjang gelombang tertentu garis-garis spektrum dapat dilihat. Ini adalah salah satu bukti dari teori mekanika kuantum.

The following titles, all by working physicists, attempt to communicate quantum theory to lay people, using a minimum of technical apparatus.

Chester, Marvin (1987) Primer of Quantum Mechanics. John Wiley. ISBN 0-486-42878-8

Richard Feynman, 1985. QED: The Strange Theory of Light and Matter, Princeton University Press. ISBN 0-691-08388-6. Four elementary lectures on quantum electrodynamics and quantum field theory, yet containing many insights for the expert.

Ghirardi, GianCarlo, 2004. Sneaking a Look at God's Cards, Gerald Malsbary, trans. Princeton Univ. Press. The most technical of the works cited here. Passages using algebra, trigonometry, and bra–ket notation can be passed over on a first reading.

N. David Mermin, 1990, "Spooky actions at a distance: mysteries of the QT" in his Boojums all the way through. Cambridge University Press: 110-76.

Victor Stenger, 2000. Timeless Reality: Symmetry, Simplicity, and Multiple Universes. Buffalo NY: Prometheus Books. Chpts. 5-8. Includes cosmological and philosophical considerations.