English

The Weyl calculus for group generators satisfying the canonical commutation relations

Functional Analysis 2018-06-05 v1 Mathematical Physics math.MP

Abstract

Classical pseudo-differential calculus on Rd\mathbb{R}^{d} can be viewed as a (non-commutative) functional calculus for the standard position and momentum operators (Q1,,Qd)(Q_{1}, \dots , Q_{d}) and (P1,,Pd)(P_{1}, \dots , P_{d}). We generalise this calculus to the setting of two dd-tuples of operators A=(A1,,Ad)A=(A_{1}, \dots , A_{d}) and B=(B1,,Bd)B=(B_{1}, \dots , B_{d}) acting on a Banach space XX such that iA1,,iAdiA_{1}, \dots , iA_{d} and iB1,,iBdiB_{1}, \dots , iB_{d} generate bounded C0C_0-groups satisfying the Weyl canonical commutation relations eisAjeitAk=eitAkeisAje^{isA_j}e^{itA_k} = e^{itA_k}e^{isA_j}, eisBjeitBk=eitBkeisBje^{isB_j}e^{itB_k} = e^{itB_k}e^{isB_j}, and eisAjeitBk=eistδjkeitBkeisAje^{isA_j}e^{itB_k} = e^{-ist \delta_{jk}} e^{itB_k}e^{isA_j} (1j,kd)(1\le j,k\le d). We show that the resulting calculus aa(A,B)L(X)a\mapsto a(A,B) \in \mathscr{L}(X), initially defined for Schwartz functions aS(R2d)a\in \mathscr{S}(\mathbb{R}^{2d}), extends to symbols in the standard symbol class S0S^{0} of pseudo-differential calculus provided appropriate bounds can be established. We also prove a transference result that bounds the operators a(A,B)a(A,B) in terms of the twisted convolution operators Ca^C_{\widehat{a}} acting on L2(R2d;X)L^{2}(\mathbb{R}^{2d};X). We apply these results to obtain RR-sectoriality and boundedness of the HH^{\infty}-functional calculus (and even the H\"ormander calculus), for the abstract harmonic oscillator L=12j=1d(Aj2+Bj2)12dL = \frac12\sum_{j=1}^d (A_j^2+B_j^2)-\frac12d.

Keywords

Cite

@article{arxiv.1806.00980,
  title  = {The Weyl calculus for group generators satisfying the canonical commutation relations},
  author = {Jan van Neerven and Pierre Portal},
  journal= {arXiv preprint arXiv:1806.00980},
  year   = {2018}
}

Comments

38 pages, submitted for publication

R2 v1 2026-06-23T02:17:49.829Z