Some extensions of the uncertainty principle

Steeve Zozor, Mariela Portesi, Christophe Vignat

Published 2007-09-19, updated 2008-04-02Version 2

We study the formulation of the uncertainty principle in quantum mechanics in terms of entropic inequalities, extending results recently derived by Bialynicki-Birula [1] and Zozor et al. [2]. Those inequalities can be considered as generalizations of the Heisenberg uncertainty principle, since they measure the mutual uncertainty of a wave function and its Fourier transform through their associated R\'enyi entropies with conjugated indices. We consider here the general case where the entropic indices are not conjugated, in both cases where the state space is discrete and continuous: we discuss the existence of an uncertainty inequality depending on the location of the entropic indices $\alpha$ and $\beta$ in the plane $(\alpha, \beta)$. Our results explain and extend a recent study by Luis [2], where states with quantum fluctuations below the Gaussian case are discussed at the single point $(2,2)$.