# Exorcizing ghost waves

## TL;DR

This paper clarifies that electromagnetic ghost waves are actually nonuniform plane waves existing in isotropic dielectric materials, emphasizing their known association with propagating and evanescent fields.

## Contribution

It provides a clear explanation that ghost waves are not new phenomena but are well-understood nonuniform plane waves in dielectric media.

## Key findings

- Ghost waves are nonuniform plane waves.
- They are associated with both propagating and evanescent fields.
- This understanding applies to isotropic dielectric materials.

## Abstract

The so-called electromagnetic ghost waves are simply electromagnetic nonuniform plane waves, whose association with both propagating and evanescent fields has long been known, even for isotropic dielectric materials that are non-dissipative.