**By Caitlin French**

### Introduction to Quantum Mechanics

Quantum Mechanics is the mathematical description of the structure and interactions of particles on atomic and subatomic scales.

It developed from Planck’s suggestion that energy is made up of individual units (quanta), Einstein’s photoelectric effect, de Broglie’s proposal of wave-particle duality of both energy and matter and Heisenberg’s uncertainty principle.

There has been much philosophical debate about the different interpretations of quantum mechanics, ranging from Bohr’s Copenhagen interpretation (criticised using the Schrödinger’s cat thought experiment) to the Many Worlds theory. Different formulations of quantum mechanics came about, including Heisenberg’s matrix mechanics and Feynman’s sum over histories or path integral approach.

Quantum mechanical processes are extremely important, having applications in computers and also in keeping us alive, as quantum tunneling allows nuclear fusion in the Sun.