Refraction in spacetime

TL;DR

This paper explores wave-like phenomena such as refraction, interference, and diffraction in spacetime, demonstrating their analogs in quantum particles' dynamics and offering new insights into quantum time evolution.

Contribution

It introduces the concept of spacetime refraction and birefringence in quantum particles, expanding the understanding of wave phenomena in quantum time evolution.

Findings

Spacetime refraction analogs observed in quantum scattering

Birefringence in spacetime demonstrated for spin-1/2 particles

Provides a new perspective on quantum time evolution

Abstract

Refraction, interference, and diffraction serve as distinguishing features for wave-like phenomena. While they are normally associated only with a purely spatial wave-propagation pattern, analogs to interference and diffraction involving the spatio-temporal dynamics of waves in one dimension (1D) have been pointed out. Here we complete the triplet of analogies by discussing how spatio-temporal analogs to refraction are exhibited by a quantum particle in 1D that is scattering off a step barrier. Similarly, birefringence in spacetime occurs for a spin-1/2 particle in a magnetic field. These examples serve to illustrate basics of quantum time evolution from a new perspective.