His contributions to the study of diabetes are unforgettable: Who is Jean Baptiste Biot?

(1774-1862) French physicist. He discovered the magnetic field law and the light polarization properties of solutions. He was born on April 21 in Paris. He began his education at College Louis-le-Grand. Although he left school in 1791, he continued to take private lessons in mathematics. He voluntarily enlisted in the army in 1792. In 1794 he entered the newly founded Ecole Polytechnique.

When he graduated in 1797, he was appointed professor of mathematics at the University of Beauvais. In 1800, at the age of 26, he was appointed as the chair of mathematical physics at the College de France. He became a member of the Academy of Sciences in 1803. He was appointed professor of astronomy to the Faculte des Sciences in 1808 and taught physics from 1817-1826 on optics, sound, and magnetism. He was the dean of this faculty from 1840 until his retirement in 1849. He died in Paris on February 3, 1862.

Although Biot has also worked in the fields of mathematics and astronomy, his most important contributions are in the field of physics. In 1804, together with Gay Lussac, he was able to ascend to an altitude of 4000 meters in a hydrogen-filled balloon to determine the correlation of the Earth's magnetic field intensity with altitude. As a result of this initiative, where the balloon was used for scientific purposes for the first time, it was understood that the magnetic field intensity changes little in height, and information was provided on the qualities and chemical structure of the upper atmosphere.

Working on the thermal conductivity of metal rods in the same year, Biot made mathematical definitions on this subject. Together with Arago, they determined the refractive index of gases and calculated the densities of air and various gases precisely. In 1806, the Department of Longitudes sent Biot and his assistant Arago to Spain to measure the meridian arc. Biot, who also made important contributions to the measurement of the speed of sound, also carried out mathematical studies on this subject. In 1820, together with Savart (1791-1841), they showed that the magnetic field intensity is inversely proportional to the square of the distance, as a result of their experiments with magnets placed at various distances to calculate the magnetic field intensity created by a current flowing conductor. These discoveries are known as the Biot-Savart law, which is one of the fundamental laws of electromagnetics.

One of Biot's most important works was research on the polarization of light, which the "Royal Society" awarded him with the Rumford Medal in 1840. In this work, Biot found that the rotation of the polarization plane varies flat with the thickness of the crystal and is inversely proportional to the square of the wavelength, which leads to the polarization of light.

He also determined that the rotation in light passing through two separate crystal layers is the arithmetic sum of the rotation caused by each layer. The results of these investigations could not be explained by the particle theory of light, which Biot advocated. Yet he never adopted the wave theory of light proposed by Biot Young. Arago, who was one of the strongest advocates of the particle theory together with Laplace, later successfully explained the polarization phenomenon with the wave theory. Biot's theoretical problems did not hinder his productive work on polarization. As a matter of fact, with his research in 1815, he determined that some materials other than quartz also had optical activities. A few of these are alcohol solutions of camphor and lemon oil, turpentine and sugar solutions.

Biot also revealed that the rotation of the polar plane is proportional to the density of the fluid and the length of the tube in which this solution is contained. In this way, it was possible to determine the densities of the solutions without chemical intervention. In particular, the ability to measure the amount of sugar in sugar solutions was later used in the study of diabetes.