Abstract

We introduce a multi-parameter family of bases in the Hilbert space L2(R) that are associated to a set of Hermite functions, which also serve as a basis for L2(R). The Hermite functions are eigenfunctions of the Fourier transform, a property that is, in some sense, shared by these “generalized Hermite functions”. The construction of these new bases is grounded on some symmetry properties of the real line under translations, dilations and reflexions as well as certain properties of the Fourier transform. We show how these generalized Hermite functions are transformed under the unitary representations of a series of groups, including the Heisenberg–Weyl group and some of their extensions.

Highlights

  • We study the relations between certain physical relevant lowdimensional Lie groups, in connection to affine transformations on the whole real line (R) and their representations on the Hilbert space L2 (R) as well as to other notions as the Hermite functions, other bases in L2 (R) and the eigenfunctions of the Fourier transform

  • As a consequence of these relations, some invariance properties are disclosed. These invariance properties come from the options between four types of freedom. These are: (i) the freedom to choose between coordinate and momentum representations and the respective bases determined by each of these representations; (ii) the freedom to choose an origin on the real line when using any of these two representations; (iii) the freedom to choose the units of length on R; and (iv) the freedom to choose an orientation on the line

  • We considered the symmetry under Fourier Transform for the Hermite functions

Read more

Summary

Introduction

We study the relations between certain physical relevant lowdimensional Lie groups, in connection to affine transformations on the whole real line (R) and their representations on the Hilbert space L2 (R) as well as to other notions as the Hermite functions, other bases in L2 (R) and the eigenfunctions of the Fourier transform. The conclusion is that X and P, along with the central operator I, determine the Lie algebra for the Heisenberg–Weyl group H (1) In this context, we say that the real line, meaning the space L2 (R), supports a unitary representation of H (1). Consistency with Fourier transform invariance implies that k0 = k−1 This suggests a result that shall become evident soon, which is that the algebra describing e o (1), i.e., the Heisenberg–Weyl group enlarged the invariance in the real line has to be H with dilatations. We need to introduce orientation invariance and negative values of k for dilatations in our picture This is done by means of the parity operator P , where the action of P on the continuous bases is given by P | x i = | − x i and P | pi = | − pi. We give our concluding remarks in the final Section 6

From the Translation Group to the Heisenberg–Weyl Group
The Group E
The Heisenberg–Weyl Group and Its Extensions
The Heisenberg–Weyl Group: A Matrix Realization
The Extended Heisenberg–Weyl Group
The Heisenberg–Weyl Algebras
Unitary Representations of the Heisenberg–Weyl Groups
UIR of the Heisenberg–Weyl Group with Dilations H
UR of the Extended Heisenberg–Weyl Group H
Unitary Representations of H
A Generalization of the Hermite Functions
Generalized Hermite Functions
Generalized Hermite Polynomials
Representations on a Rigged Hilbert Space
Concluding Remarks
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.