In 1913, Niels Bohr proposed a model of the hydrogen atom that introduced the concept of quantized energy levels. Bohr assumed that the energy which an electron in an atom may have is quantized, i.e. it can possess only certain amounts of energy. Bohr...

In 1913, Niels Bohr (1885-1962) proposed a model of the hydrogen atom that introduced the concept of quantized energy levels. Bohr assumed that the energy which an electron in an atom may have is quantized, i.e. it can possess only certain amounts of...

A major characteristic of a PRIVATE GOOD: one person’s consumption excludes others’ consumption, e.g. my consumption of a piece of fruit excludes your consumption of it. PUBLIC GOODS are non-exclusive, e.g. my consumption of the benefit of...

The Pauli exclusion principle enabled the quantum structure of the atom to be understood. It provided a mechanism to explain the variety and behavior of the chemical elements, and it gave a theoretical basis for the periodic table. It was one of the...

Introduction to... Mathematical formulation...

Testing the Pauli exclusion principle The Pauli exclusion principle stands at the heart of modern molecular, atomic and nuclear physics. By insisting that no two electrons, protons or neutrons can occupy exactly the same quantum state, the principle explains why matter doesn't...

Violating a not-so-exclusive exclusion principle The Pauli exclusion principle stands at the basis of the structure and stability of matter. It prevents, atoms, nuclei and larger structures, up to and including neutron stars, from collapsing on themselves. It does so by decreeing...