An animated Google Doodle is cutting a colourful dash on Google’s homepage today to celebrate what would have been the 155th birthday of Heinrich Rudolf Hertz, the physicist who clarified and expanded the electromagnetic theory of light, paving the way for the invention of the telegraph, radio, and, latterly, television.
The electromagnetic theory had first been posited by the Scottish mathematician and physicist James Clerk Maxwell. It was Maxwell who demonstrated that electric and magnetic travel through space in the form of waves, and at the constant speed of light. Maxwell’s findings were published in A Dynamical Theory of the Electromagnetic Field in 1865.
On 22 February 1857, Hertz was born in Hamburg, Germany. His father, Gustav Ferdinand Hertz, was a writer and later a senator, while his mother was Anna Elisabeth Pfefferkorn.
Showing an aptitude for the sciences as well as languages, Hertz studied sciences and engineering in the cities of Dresden, Munich and Berlin.
He obtained his PhD from University of Berlin and subsequently remained there to study under Hermann von Helmholtz, the German physician and physicist known for his theories on the conservation of energy.
Then, in 1883, Hertz took up a post as a lecturer in theoretical physics at University of Kiel.
It was in 1885 that he took up a full professorship at University of Karlsruhe, where he discovered electromagnetic waves.
The Google Doodle in honour of physicist Heinrich Rudolf Hertz
Maxwell’s electromagnetic theory had challenged experimentalists to generate and detect electromagnetic radiation using some form of electrical apparatus.
Hertz made the first successful attempt to generate and detect electromagnetic radiation in 1886. For his radio wave transmitter, he used a high-voltage induction coil, a condenser and a spark gap. The aim was to cause a spark discharge between the spark gap’s poles oscillating at a frequency determined by the values of the capacitor and the induction coil.
In his later, more advanced, experiments, Hertz measured the velocity of electromagnetic radiation. He determined it to be the same as light’s velocity. In 1886, he developed the Hertz antenna receiver.
To celebrate his contribution, the unit of frequency – one cycle per second – is termed the ‘hertz’.
Between 1886 and 1889, Hertz also wrote two papers on what would later be known as the field of contact mechanics.
In 1892, he developed an infection and underwent operations. However, he died at the age of 36 in Bonn, Germany, from Wegener’s granulomatosis.
He was survived by his wife, Elizabeth and their two daughters, Elizabeth Joanna and Mathilde.
Hertz’s nephew Gustav Ludwig Hertz was the German experimental physicist who won the Nobel Prize in Physics in 1925.