Dan Margalit is a professor in the School of Mathematics. 

Margalit's research area is topology. He studies the properties of shapes that persist even when the shapes are stretched or bent. 

For example, two metal rings that are linked stay linked even if you bend or stretch the metal. A typical question in topology is the following: Someone hands you two rings made of metal; if you are allowed to bend and stretch the metal, can you pull the rings apart or not? 

Most of Margalit's research in topology is about surfaces. The surface could be that of a ball or a donut. Surfaces are central in mathematics. They can describe the possible motions of a robot arm or all the possible solutions of a polynomial.

Margalit's particular research is on the symmetries of surfaces. Some symmetries of surfaces are easy to understand. But when bending and stretching are allowed, the symmetries are more challenging.

For Margalit, "mathematics is important because it describes the world in a beautiful and coherent way. Even the most far-fetched and abstract mathematical ideas can make their way into everyday life."

In Episode 9, Margalit talks about the beauty of mathematics and offers advice to overcome "math phobia."

Take a listen at sciencematters.gatech.edu.

Enter to win a prize by answering the question for Episode 9: 

According to Episode 9, what group of people can’t tell the difference between a coffee cup and a donut?

Submit your entry by 11 AM on Monday, Oct. 22, at sciencematters.gatech.edu.