Sally Zhu
The Harker School
San Jose, California
色色视频 Sally Zhu
Sally studied the patterns made by the waves that flow below the water鈥檚 surface, called internal waves, in a hypothetical two-dimensional fish tank, and how they can go from choppy to smooth as they bounce off the tank鈥檚 walls. Sally believes that this could help scientists analyze waves in the ocean.
On the Smoothness and Regularity of the Chess Billiard Flow and the Poincar茅 Problem
Sally Zhu, 17, of Saratoga, made waves with her Regeneron Science Talent Search mathematics project. Many people are familiar with how waves move on the surface of water in a fish tank, but there are also waves that travel below the surface, called internal waves. Understanding these waves mathematically is difficult because they bounce off of walls in an extremely complex way. In her project, Sally addressed this difficulty by showing that internal waves that undergo 鈥渃hess billiard flow鈥� in a two-dimensional square fish tank will always go from choppy to smooth if a certain number, called the rotation number, of the tank is a Diophantine number (an irrational number that cannot be neatly approximated with rational numbers). Not only did Sally add to the field theoretically, but she also performed numerical experiments on a computer and generated plots to intuitively explain her theoretical results, which she hopes will help scientists in fluid dynamics and oceanography.
The daughter of Huican Zhu and Hong Wei, Sally attends The Harker School in San Jose.
Beyond the Project
Sally is a published first-author in Research Notes of the American Astronomical Society. She is also editor-in-chief for her high school鈥檚 online news site, the Harker Aquila.
FUN FACTS: Sally has a 鈥減retty extensive鈥� puzzle collection that includes Rubik鈥檚 cubes, jigsaw puzzles and more! When she needs to de-stress, she says she turns on music and works on a puzzle.
