Born in 1775 in Lyon, France, André-Marie Ampère -- AMA to his friends -- never went to school; he figured it out all by himself in the well-garnished family library.

He Publishes His First Paper at the Age of 13

At the age of 12, AMA becomes interested in mathematics and, a year later, publishes his first paper. During the French Revolution, AMA, sixteen years old, proposes a new decimal measurement system. When he is 18, his father is guillotined, and the family ruined. AMA turns to studying botany, inventing scientific instruments and observing the stars; he learns Greek and Italian and creates a universal language. He studies Latin poetry and even writes a tragedy criticizing Christopher Columbus.

Some people say that his attention is dispersed, but not AMA; he goes on to study chemistry in general and carbon oxide in particular. When, at the age of about 25, AM finally goes to school, he goes as a teacher, not as a student.

 
Ampère on an Eastern Germany stamp
André-Marie Ampère is as defunct as the DDR.

Ørsted’s discovery

In 1820 the Danish physicist Hans Christian Ørsted discovers that an electric current deflects a nearby magnetic needle. At that time AMA lives in Paris and works on speculative philosophy and its application to other fields of science. Even without Twitter Ørsted’s discovery goes viral and AM learns about it at the beginning of September 1820.

Inspired by the exciting news, AMA drops everything and sets off to repeat Ørsted’s experiments. He realizes quickly that a wire carrying a current behaves like a magnet. From this he concludes that two of these wires in parallel should attract or repel each other depending on whether the currents flow in the same direction or not. Also, he deduces that such a wire would be influenced by the Earth’s magnetic field, exactly like a compass needle.
 
André-Marie Ampère on a French stamp
André-Marie Ampère
depicted on a French stamp.

André-Marie Ampère coins the term electrical current

About a week later, AMA presents his first findings. AMA was on a roll and after another week of frantic work presents a second paper in which he coins the term electrical current. In the weeks that follow he invents techniques for measuring such currents and develops methods for magnetizing steel. By the end of 1820, AMA wraps it all up in a paper and the field of electrodynamics was born.

During the following years, AMA continues to experiment with electricity and magnetism and comes up with the hypothesis that electrical current consists of some sort of electrodynamic molecule that is being pushed through a conductor. In 1827 he publishes his magnum opus: Memoir on the Mathematical Theory of Electrodynamic Phenomena, Uniquely Deduced from Experience. Today, this is considered to be the founding treatise of electrodynamics.

A Real Science Hero

Being an SI base unit like Volta, today Ampère’s name is mainly connected to electrical current, but his scientific oeuvre goes way beyond that. He has made important contributions to mathematics and physics, and played a major role in the discoveries of chlorine, fluorine and iodine. André-Marie Ampère -- passed away in 1836 -- was one of those truly great minds that gave science a big push forward.
 
André-Marie Ampère on a stamp from Monaco
Monaco celebrated the 200th anniversary of André-Marie Ampère with a stamp.

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