Evgenii Landis facts for kids
Evgenii Mikhailovich Landis (born October 6, 1921 – died December 12, 1997) was a brilliant Soviet mathematician. He spent most of his career studying partial differential equations. These are special math problems that help describe how things change in the world, like heat flowing or waves moving.
A Life in Math
Landis was born in Kharkiv, a city in the Ukrainian SSR, which was part of the Soviet Union. He studied and worked at Moscow State University. His main teachers there were Alexander Kronrod and later Ivan Petrovsky.
Important Discoveries
In 1946, Landis and Kronrod made an important discovery together. They rediscovered something called Sard's lemma. This math rule helps understand how smooth functions behave. At that time, this rule was not known in the Soviet Union.
Later in his career, Landis focused on other big math ideas. He worked on "uniqueness theorems" for certain types of differential equations. These theorems help prove that there is only one possible solution to a math problem. He also explored Harnack inequalities and Phragmén–Lindelöf type theorems. These are advanced math tools used to understand how solutions to equations behave.
The AVL Tree
One of Landis's most famous inventions was not just in pure math. With his colleague Georgy Adelson-Velsky, he created a special way to organize information for computers. This is called the AVL tree data structure. The "AVL" in its name comes from the first letters of their last names: Adelson-Velsky Landis. AVL trees are still used today to keep data sorted and easy to find quickly.
Evgenii Landis passed away in Moscow. Many students learned from him, including the well-known mathematician Yulij Ilyashenko.
