Thomas Stieltjes

Thomas Stieltjes was a mathematician known for his work in analysis, particularly in developing the Stieltjes integral, a generalization of the Riemann integral. This integral allows for measuring the area under a curve even when the function has jumps or discontinuities, by integrating with respect to another function instead of just the variable. His work provides a powerful framework for probability, spectral theory, and other areas of mathematics where traditional integrals are insufficient. Essentially, Stieltjes expanded how we can measure and analyze more complex functions and data, enhancing mathematical tools for various scientific fields.