Hydrogen A to Z Series: N For Noether
By: GenH2 Staff
Read Time: 3 minutes
Defining Hydrogen from A-Z: N is for Noether
Continuing in our Defining the Hydrogen Economy series, today we revisit the letter N and will be learning more about one of the greatest mathematicians of the 20th century: Emmy Noether.
Amalie Emmy Noether was born on March 23, 1882 in Erlangen, Germany, and was a mathematician whose innovations in higher algebra gained her recognition as the most creative abstract algebraist of modern times. Noether was certified to teach English and French in schools for girls in 1900, but she instead chose to study mathematics at the University of Erlangen (now University of Erlangen-Nürnberg). She earned her doctorate with a dissertation on algebraic invariants in 1907 and then after graduation taught several years without pay because women were not technically allowed to teach at universities in Germany at the time.
In 1915, one of the leading mathematicians of the age, David Hilbert, invited her to join him at the University of Göttingen. Liberalized laws in Germany following World War I allowed Noether to be granted a teaching position (with little pay), and with the condition that she could only lecture in classes under Hilbert’s name. Hilbert soon used her knowledge of invariants to help them explore the mathematics behind Albert Einstein’s recently published theory of general relativity. Despite fervent objections by some faculty to a woman teaching at the university, Noether would remain there until 1933.
In 1918, Noether discovered that if the Lagrangian (a quantity that characterizes a physical system; in mechanics, it is kinetic minus potential energy) does not change when the coordinate system changes, then there is a quantity that is conserved. For example, when the Lagrangian is independent of changes in time, then energy is the conserved quantity. This relation between what are known as the symmetries of a physical system and its conservation laws is known as Noether’s theorem and has proven to be a key result in theoretical physics.
Because her work relies on symmetry and conservation laws, nearly every modern physicist uses Noether’s theorem. Every time scientists use a symmetry or a conservation law, from the quantum physics of atoms to the flow of matter on the scale of the cosmos, Noether’s theorem is present. The law of conservation of energy is the direct mathematical consequence of the translational symmetry of the quantity conjugate to energy. The greatest success of Noether’s theorem came with quantum physics, and especially the particle physics revolution that rose after Noether’s death in 1935 after coming to America in 1933.
This theorem and pioneers like Noether help us better understand the mystery of energy and how important the use of energy or an energy carrier is to cryogenics, and that cryogenics and energy are like two sides of the same coin. GenH2 takes advantage of the energy density of liquid hydrogen and how energy and time (savings) are directly related as we provide liquid hydrogen infrastructure solutions and products.
