Abstract
We turn now to operators on an LVS. To start with, we need a number of simple definitions. Most of these are obvious in the case of finite-dimensional vector spaces. But the case of infinite-dimensional spaces is nontrivial, and due care must be exercised. As always, I shall merely describe and list some relevant results in brief, without getting into technical details and proofs of assertions, or the formal mathematics. These details and formal proofs are, however, particularly important at least for some of the topics in this chapter. It is therefore advisable to supplement the discussion given here with more extended treatments to be found in standard texts on operator algebra and functional analysis (see, e.g., Bibliography).
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
There is an important matter of notation involved here. See the Note that follows below, after Eq. (14.9).
- 2.
From now on, I will drop the overhead caret that we have used to denote operators. You can identify them from the context.
- 3.
What the particular problem of the harmonic oscillator does is to provide two “dimensionful” parameters—the mass m and the natural frequency \(\omega \) of the oscillator. These parameters, in combination with \(\hbar \), provide natural scales of length and momentum in the oscillator problem, proportional to \((\hbar /m\omega )^{1/2}\) and \((m\hbar \omega )^{1/2}\), respectively.
- 4.
As I have mentioned earlier, the exact expression for \(\Phi _n(x)\) is given in Eq. (16.47) of Chap. 16, Sect. 16.2.5.
- 5.
As a linear combination of the eigenfunctions concerned, with unique expansion coefficients.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
Copyright information
© 2020 Authors
About this chapter
Cite this chapter
Balakrishnan, V. (2020). Linear Operators on a Vector Space. In: Mathematical Physics. Springer, Cham. https://doi.org/10.1007/978-3-030-39680-0_14
Download citation
DOI: https://doi.org/10.1007/978-3-030-39680-0_14
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-030-39679-4
Online ISBN: 978-3-030-39680-0
eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)