Measurements, errors, and negative kinetic energy

TL;DR

This paper explores measurement errors in quantum mechanics, revealing that unphysical measurement outcomes like negative kinetic energy can occur and form consistent patterns, providing new insights into quantum particle behavior.

Contribution

It introduces a novel analysis of measurement errors, demonstrating that unphysical values such as negative kinetic energy can be consistent and experimentally observed in quantum systems.

Findings

Negative kinetic energy values observed in experiments

Unphysical measurement outcomes can form consistent patterns

Supports the concept of weak values in quantum measurements

Abstract

An analysis of errors in measurement yields new insight into the penetration of quantum particles into classically forbidden regions. In addition to ``physical" values, realistic measurements yield ``unphysical" values which, we show, can form a consistent pattern. An experiment to isolate a particle in a classically forbidden region obtains negative values for its kinetic energy. These values realize the concept of a {\it weak value}, discussed in previous works.