What new discoveries have broken physics

Experiments: The 10 Most Breakthrough Physical Discoveries

1. The discovery of electromagnetic waves |

Only a tiny spark between two wires brought Heinrich Hertz to the fact that he had witnessed electrical radiation. Of course, he had no idea how much this discovery would change the world.

At the University of Karlsruhe, the 30-year-old professor attempted electrical discharge in 1887. To do this, he interrupted a current-carrying coil and generated a spark. This was nothing new and was already known to other scholars. By chance, however, Hertz observed something else: there was also a radio link on an additional, also interrupted coil nearby. Just at the same moment as the spark jumped over at the first coil. The second coil was not connected to any circuit, so Hertz deduced that the electricity must have been transmitted from one coil to the other in some form of radiation.

In the years that followed, the bustling professor undertook many more experiments that undoubtedly showed that he was actually observing electromagnetic waves that were propagating in space. 22 years earlier, physicist James Clerk Maxwell had concluded from his equations that such waves must exist; also that radio, x-ray or light rays, for example, must be different manifestations of the same phenomenon. However, Maxwell did not live to see the evidence that Hertz finally produced.

Hertz constructed, for example, a transmitter that could generate waves and a receiver that picked up these signals. He recognized that the received signal is particularly strong at a certain distance and that the receiver was in a sense in resonance with the transmitter. He also demonstrated that electromagnetic waves can be reflected, refracted and focused - just like rays of light.

The omnipresence of smartphones, WLAN and Co. shows that a modern world is inconceivable without the use of electromagnetic waves. And the name of the associated unit of measurement reminds us to whom we owe the knowledge of its existence: the genius Heinrich Hertz, who died at the age of 37.