Happy birthday to Olga Ladyzhenskaya (1922-2004), a #mathematician who overcame personal tragedy, faced Soviet totalitarianism & the catastrophic political upheaval of the 20th century to make a huge impact on the math, making important contributions to study of partial differential equations (PDEs). She changed the way PDEs are examined & popularized the notion of weak solutions (which satisfy the equations but may not be differentiable).🧵








