James Maxwell Anniversary


Scottish scientist James Maxwell’s studies of electromagnetism in the 1860s and 1870s laid the foundations for electrical and telecommunications engineering, special relativity, and quantum mechanics.

Today, on the occasion of his 191st anniversary, we want to emphasize his most disruptive discovery that began the profound transformation of scientific knowledge about the nature of the Universe:

“Electromagnetic fields travel at the speed of light”

This propagation speed is a constant that is obtained from Maxwell’s Equations from the electrical permittivity (ε0) and the magnetic permeability (μ0), according to the formula c=1/√(ε0μ0).

That the speed of light c depends on two properties of empty space, such as its electrical permittivity and magnetic permeability, suggested that the speed of light is more than just a characteristic of light.

Today it is known that the constant c is the ‘speed of causality’, the only speed at which massless particles can travel through space, such as photons, but also gravitational waves and gluons.

Currently we can find examples of the application of Maxwell’s Equations and the new theories of quantum mechanics and electrodynamics (QED) in the most diverse fields of science, such as the study of bird migration, as we will see below.

According to an article published in the April 2022 issue of Scientific American magazine, the results of the latest research point to the existence of an internal magnetic compass in birds whose mechanism is based on radical pairs, which are molecules with odd (unpaired) electrons (so having spin and magnetic moment) created simultaneously in a chemical reaction.

In radical pairs, a quantum effect discovered in the 1960s is produced, consisting of the continuous inversion of spins, with such extreme sensitivity that it can detect a magnetic field as weak as that generated by the molten core of the Earth.

The radical pairs are photochemically formed in the birds’ eyes, producing the magnetoreception that will allow them to determine their position and direction to navigate with an extraordinary precision of centimeters over distances of thousands of kilometers.

On this day of tribute to James Maxwell, we want to thank all the scientists before, contemporary and after him who contributed their discoveries to the development of theories that allow us to understand electromagnetic fields and their applications in the real world.

Happy Anniversary James!