Abstract
We express the condition for a phase space Gaussian to be the Wigner distribution of a mixed quantum state in terms of the symplectic capacity of the associated Wigner ellipsoid. Our results are motivated by Hardy’s formulation of the uncertainty principle for a function and its Fourier transform. As a consequence we are able to state a more general form of Hardy’s theorem.
Similar content being viewed by others
References
Bonami A., Demange B. and Jaming P. (2003). Hermite functions and uncertainty principles for the Fourier and the windowed Fourier transform. Rev. Mat. Iberoamericana 19(1): 23–55
Fefferman C. and Phong D.H. (1981). The uncertainty principle and sharp Gårding inequalities. Comm. Pure Appl. Math. 75: 285–331
Bayen F., Flato M., Fronsdal C., Lichnerowicz A. and Sternheimer D. (1978). Deformation theory and quantization. I. Deformation of symplectic structures. Ann. Phys. 111: 6–110
Bayen F., Flato M., Fronsdal C., Lichnerowicz A. and Sternheimer D. (1978). Deformation theory and quantization. II Physical Applications. Ann. Phys. 110: 111–151
Folland G.B. (1989). Harmonic Analysis in Phase space. Annals of Mathematics Studies. Princeton University Press, Princeton, NJ
de Gosson M. (2005). Cellules quantiques symplectiques et fonctions de Husimi–Wigner. Bull. Sci. Math. 129: 211–226
de Gosson M. (2005). On the Weyl representation of metaplectic operators. Lett. Math. Phys. 72: 129–142
de Gosson, M.: Uncertainty principle, phase space ellipsoids and Weyl calculus. Operator Theory: Advances and Applications, vol. 164, pp. 121–132. Birkhäuser, Basel (2006)
de Gosson, M.: Symplectic geometry and quantum mechanics. Operator Theory: Advances and Application (subseries: “Advances in Partial Differential Equations”), vol. 166. Birkhäuser, Basel (2006)
Gromov M. (1985). Pseudoholomorphic curves in symplectic manifolds. Invent. Math. 82: 307–347
Hardy G.H. (1933). A theorem concerning Fourier transforms. J. Lond. Math. Soc. 8: 227–231
Gröchenig K. and Zimmermann G. (2001). Hardy’s theorem and the short-time Fourier transform of Schwartz functions. J. Lond. Math. Soc. (2) 63: 205–214
Hofer H. and Zehnder E. (1994). Symplectic Invariants and Hamiltonian Dynamics. Birkhäuser, Boston
Leray J. (1981). Lagrangian Analysis and Quantum Mechanics, a mathematical structure related to asymptotic expansions and the Maslov index. MIT Press, Cambridge
Littlejohn R.G. (1986). The semiclassical evolution of wave packets. Phys. Rep. 138(4–5): 193–291
Messiah, A.: Mécanique Quantique vol. 1. Dunod, Paris, (1995) [English translaton: Quantum Mechanics, North–Holland (1991)]
Narcowich F.J. and O’Connell R.F. (1986). Necessary and sufficient conditions for a phase-space function to be a Wigner distribution. Phys. Rev. A 34(1): 1–6
Narcowich, F.J.: Geometry and uncertainty. J. Math. Phys. 31(2), (1990)
Polterovich L. (2001). The Geometry of the Group of Symplectic Diffeomorphisms. Lectures in Mathematics. Birkhäuser, Boston
Radha R. and Thangavelu S. (2004). Hardy’s inequalities for Hermite and Laguerre expansions. Proc. Am. Math. Soc. 132(12): 3525–3536
Simon R., Sudarshan E.C.G. and Mukunda N. (1987). Gaussian–Wigner distributions in quantum mechanics and optics. Phys. Rev. A 36(8): 3868–3880
Simon R., Mukunda N. and Dutta B. (1994). Quantum Noise Matrix for Multimode Systems: U(n)-invariance, squeezing and normal forms. Phys. Rev. A 49: 1567–1583
Williamson J. (1936). On the algebraic problem concerning the normal forms of linear dynamical systems. Am. J. Math. 58: 141–163
Author information
Authors and Affiliations
Corresponding author
Additional information
The authors were supported under the EU-project MEXT-CT-2004-51715.
Rights and permissions
About this article
Cite this article
de Gosson, M., Luef, F. Quantum States and Hardy’s Formulation of the Uncertainty Principle: a Symplectic Approach. Lett Math Phys 80, 69–82 (2007). https://doi.org/10.1007/s11005-007-0150-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11005-007-0150-6