“crackpots” who were right 12: Georg Ohm

The name of Ohm is well-known to electricians and physicists because of Ohm’s Law and the metric unit used to measure resistance; the Ohm.  The Law states that the current through a conductor is proportional to the voltage applied leading to the equation V = IR, a simple rule that is easy to test with some batteries, some wires and a current meter. It is therefore quite surprising to learn that when Georg Ohm published his work in 1827 it was highly criticised for several years.

Georg Ohm, born 1787 in Bavaria, was a clever student who was largely self-taught in scientific fields and mathematics. At 26 he enrolled in the University of Erlangen. He did not take his studies very seriously with the result that his father forced him to leave and take up a poorly paid job as a teacher. However he persisted with his studies privately and received a doctorate in 1811

Realising that he was in a poverty trap that meant he could never marry, Ohm aimed to make his name in science with the hope that it would lead to a better paid position. He read the texts of the leading mathematicians and physicists of France and set about his own electrical experiments. At the time it was not so easy to produce steady voltages and accurate measurements so little was known about the flow of currents. Ohm carefully prepared samples of wire of constant composition and width and used a thermocouple to control voltages with heat. With a galvanometer he could measure the current flow through the wires as a function of voltage and length of wire. Details of the experiments were published in 1825.

Unfortunately, the scientific philosophy of the time led by Hegel in Germany did not value experiment as highly as theory. Ohm therefore sought to bolster his work with a theoretical derivation and he turned to the work of Fourier on heat conduction  as a basis for his theory. The completed work was published in 1827 as “The galvanic Circuit investigated mathematically” We now know that quantum mechanics is needed to properly treat the theory of conduction. Even primitive classical models based on kinetic atomic theory were not accessible to Ohm at the time and Ohm’s theory could never be more than a sham.

Ohm’s masterly empirical work was ignored while his theory was torn apart. His harsh critics in germany called it a “web of naked fancies”. Another reviewer said the book’s “sole effort is to detract from the dignity of nature.” The hardest blow came from the German Minister of Education who  said that “a professor who preached such heresies was unworthy to teach science.” Ohm had hoped for a new position as a university professor but now he was forced to give up even his job as a  lowly paid school teacher. His life was in ruins.

For six years he fell on hard times until he once again took up teaching at a polytechnic. Few of his German colleagues ever took back their stiff critical words, but in America and England where experimental work was more highly regarded he gradually found acclaim. In 1843 the Royal Society awarded him the Copley Medal. At that point he might have seen better fortune at home but he tempted fate with theory of acoustics that led to a dispute with  the German scientist August Seebeck. It was not until 1852 that he finally appointed to the chair of physics at the University of Munich. He died two years later. In 1881 his name was imortalised when the Ohm was officially adopted as the unit of resistance.

With hindsight, Ohm’s poor level of recognition can be attributed to a number of unfortunate political and philosophical factors: The low regard for experimental science in his homeland, his status as a self-taught amateur, perhaps his reliance on the work of French mathematicians at a time of tension between Germany and France, and even some political wranglings involving his brother. But there is also a message from his story that is relevant today. Sometimes we may be distracted from seeing a great truth in a person’s work because we are distracted by irrelevant errors. It is a lesson of importance for both the author and reviewer of any scientific work.

2 Responses to “crackpots” who were right 12: Georg Ohm

  1. nessuno says:

    I really like this series of posts. But this one is even more involving, with all these space-time travelling by Dr. Ohm!
    Thank you

    P.S. You can remove this comment after you correct the dates!

    • philipgibbs says:

      His faulty tardis jumbled up the letters of his name.
      I have now given him a more convincing timeline, thanks.

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