References
- Levine IN (2000) Quantum chemistry, 5th edn. Prentice-Hall, Upper Saddle River, NJ,
p665 - Levine IN (2000) Quantum chemistry, 5th edn. Prentice-Hall, Upper Saddle River, NJ, pp
664–695
Chapter 4, Harder Questions, Answers
Q1
Do you think it is reasonable to describe the Schr€odinger equation as a postulate of
quantum mechanics? What is a postulate?
The consensus is that the Schr€odinger equation cannot be derived, but rather it
must be (and in fact it was) arrived at by more or less plausible arguments, then
tested against experiment. Thus it can be regarded as having originated as a
postulate, but as having survived testing so thoroughly that it may now be taken
as, to all intents and purposes, correct. Detailed presentations of the historical facts
connected with the genesis of the equation are given by Moore [1] and Jammer [2].
For a perceptive exegesis of the equation see Whitaker [3].
The simplest “derivation”, given in many books, e.g. in chapter 4, was in fact
similar to that used by Schr€odinger to obtain an equation which falls short of the
relativistic Schr€odinger equation only by the absence of spin, a concept which
had not yet arisen [1]. This first quantum-mechanical wave equation is now
known as the Klein-Gordon equation, and applies to particles without spin.
References
- Moore W (1989) Schr€odinger. Life and thought. Cambridge University Press, Cambridge, UK,
chapter 6 - Jammer M (1989) The conceptual development of quantum mechanics. American Institute of
Physics, pp 257–266 - Whitaker A (1996) Einstein, Bohr, and the quantum dilemma. Cambridge University Press,
Cambridge, UK, pp 138–146
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