A friend sent me a news story with the picture of Stephen Hawking. At first I assumed it was about a new theory or a new bold hypothesis Hawking has made, like his warnings against contacting extraterrestrial life, but I found the shocking story: Stephen Hawking passed away at age 76.
He was one of the most known and best-loves public faces of science, but beyond the scientist, he was an amazing human being. He lived and worked more than 50 years beyond the doctor's forecast and in truth pushed the boundaries of what we imagine is possible for a human being.
His most famous works involved exploring the still-unknown interface of the General Theory of Relativity with quantum physics, where he connected several seemingly unrelated ideas in physics -- always a sign of genius -- to define thermodynamics for black holes. You can find a simple explanation here: https://www.physicsoftheuniverse.com/topics_blackholes_theory.html
For people who would like to see some equations, this is a nice technical review of the subject and its history: https://arxiv.org/abs/hep-th/0409024
Here is his public lecture on cosmology at Geneva University:
He will always be present in our hearts and minds.