The Particle Enigma

TL;DR

This paper discusses the historical and modern conceptual challenges of elementary particles, exploring wave-particle duality, quantum issues, and theories like string theory to deepen understanding of particle nature.

Contribution

It provides a comprehensive review of particle concepts, including classical, quantum, and string theory perspectives, highlighting unresolved issues and recent theoretical ideas.

Findings

Analysis of classical and quantum particle problems

Discussion of string theory implications for particles

Exploration of Dirac equation and chiral oscillations

Abstract

The idea that particles are the basic constituents of all matter dates back to ancient times and formed the basis of physical thought well into modern times. The debate about whether light was a wave or a stream of particles also lasted until relatively recently. It was the advent of de Broglie's work and its implications that revolutionized the concept of an elementary particle -- but unfortunately did not banish the idea of a point particle despite its difficulties in both classical and quantum physics. Some of these problems are discussed in this essay, which covers chiral oscillations, Penrose's "zigzag" picture of particles satisfying the Dirac equation, and some ideas derived from string theory.