1 2 N ov 1 99 6 The Quantum electrodynamical uncertainty relation in strong magnetic fields

We formulate according to the quantum mechanical uncertainty relation new quantum electrodynamical uncertainty relation ∆A m ·∆x m ∼ ¯ h e where A m and ∆x m ≥ l B are the pure electromagnetic 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 ∆A m .