It is shown that the observed potential drops on QHE samples can be considered as a realization of uncertainty relation for the quantized two dimensional electromagnetic potential.
We formulate according to the quantum mechanical uncertainty relation a new quantum electrodynamical uncertainty relation ΔA˘.Δl∼ℏ/e where A˘ and Δl≥lB are the electromagnetic pure gauge potential, the position uncertainty and the magnetic length, respectively. Then, we show that the observed potential drops on the edge of QHE samples are varifications of this uncertainty relation, where the quantum potential drop of the relevant component of potential can be considered as its quantum uncertainty ΔA˘.
We discuss a model where the relation between Hall potential AH = and gate potential AG, which is manifested by the stepped QHE = curve, is described by an uncertainty relation ΔAH.=ΔAG=3DB(ℏ/e).
Investigating the quantum nature of gravity is an important issue in modern physics. Recently, studies pertaining to the quantum superposition of gravitational potential have garnered significant interest. Inspired by Mari et al. [Sci. Rep. 6, 22777 (2016)] and Baym and Ozawa [Proc. Natl. Acad. Sci. U.S.A. 106, 3035 (2009)], Belenchia et al. [Phys. Rev. D 98, 126009 (2018)] considered a gedanken experiment involving such a quantum superposition and mentioned that the superposition renders causality and complementarity inconsistent. They resolved this inconsistency by considering the quantized dynamical degrees of freedom of gravity. This suggests a strong relationship between the quantum superposition of the gravitational potential and the quantization of the gravitational field. In our previous study [Phys. Rev. D 106, 125002 (2022)], we have shown that the quantum uncertainty of a field guarantees the consistency between causality and complementarity. In this study, we focus on the entanglement between two particles' states due to the electromagnetic/gravitational potential and investigate its relationship with quantum uncertainty, causality, and complementarity. Our numerical analyses show that the quantum uncertainty of the electromagnetic/gravitational field results in vacuum fluctuations and prohibits the entanglement between two particles' states when causality is satisfied. We further demonstrate that complementarity holds when the particles do not get entangled. The uncertainty relation does not cause the entanglement between two particles' states, which guarantees complementarity.
For real potentials and for arbitrary boundary conditions we point to previously noted paradoxes in applications of the Ehrenfest and Hellmann-Feynman theorems, their resolution and the role played on the consistency of quantum mechanical uncertainty relations. The paradoxes originate from a hidden non-Hermitian character of the kinetic energy operator and are resolved if the proper boundary terms (almost always discarded in the literature) are taken seriously. These non-Hermitian contributions (reflections at a deeper level of topological anomalies) follow their own patterns (for any dimensionality, for both Schroedinger and Dirac/Weyl Hamiltonians and for either continuous or lattice (tight-binding) models): they can always be written as global fluxes of certain generalized current densities. In continuous nonrelativistic cases, these have the forms that had earlier been used by Chemists to describe atomic parts of polyatomic molecules while for Dirac/Weyl or lattice models they appear to have the corresponding relativistic forms. In spite of the fact that these boundary terms originate from a deep mathematical anomaly, we point out examples where such non-Hermiticities have physical significance in Quantum Condensed Matter Physics (for both conventional and topologically nontrivial materials). In all stationary state examples considered, these non-Hermitian boundary terms have turned out to be quantized, this quantization being either of conventional or of a topological (Quantum Hall Effect (QHE)-type) origin. The latter claim is substantiated through direct application to a simple QHE arrangement (2-D Landau system in an external electric field). Finally, the non-Hermitian terms are also shown to be crucial for the consistency of the standard uncertainty relations (of Kennard/Robertson type) in multiply-connected space or, generally, in any system that satisfies the Bloch theorem.