Universality in Uncertainty Relations for a Quantum Particle
Autor: | Kechrimparis, Spiros, Weigert, Stefan |
---|---|
Rok vydání: | 2015 |
Předmět: | |
Zdroj: | J. Phys. A: Math. Theor. 49 355303 (2016) |
Druh dokumentu: | Working Paper |
DOI: | 10.1088/1751-8113/49/35/355303 |
Popis: | A general theory of preparational uncertainty relations for a quantum particle in one spatial dimension is developed. We derive conditions which determine whether a given smooth function of the particle's variances and its covariance is bounded from below. Whenever a global minimum exists, an uncertainty relation has been obtained. The squeezed number states of a harmonic oscillator are found to be universal: no other pure or mixed states will saturate any such relation. Geometrically, we identify a convex uncertainty region in the space of second moments which is bounded by the inequality derived by Robertson and Schr\"{o}dinger. Our approach not only unifies existing uncertainty relations but also leads to new inequalities for second moments. Comment: 22 pages, 4 figures. Material rearranged to match published version |
Databáze: | arXiv |
Externí odkaz: |