Explore a detailed lecture on the Harder-Narasimhan stratification of the B+dR-Grassmannian, presented by Eva Viehmann from the Technical University Munich. Delivered as part of the 2021 Fields Medal Symposium honoring Peter Scholze, this hour-long talk delves into advanced mathematical concepts at the intersection of algebraic geometry and number theory. Gain insights into the structure and properties of the B+dR-Grassmannian, and understand how the Harder-Narasimhan stratification applies to this mathematical object. Suitable for graduate students and researchers in mathematics, this lecture offers a deep dive into cutting-edge research in the field.