The Origin of Trigonometric K-matrices in Quantum Systems - Part II

Explore the mathematical foundations of trigonometric K-matrices in quantum integrable systems with boundaries during this 49-minute lecture by Bart Vlaar. Delve into the concept of integrability characterized by R-matrices, solutions to the Yang-Baxter equation, and Drinfeld's observations on universal R-matrices in quantum affine algebras. Examine the development of K-matrices as solutions to the reflection equation in systems with boundaries, tracing their study from the 1980s. Learn about recent joint work with A. Appel proving the existence of a universal K-matrix and its application in a boundary analogue of Drinfeld's approach. Understand how specifying a suitable subalgebra guarantees a "limitless supply" of trigonometric K-matrices, resulting in matrix-valued formal Laurent series K(z) satisfying Cherednik's generalized reflection equation. Gain insights into the rational dependence of K(z) on the spectral parameter for irreducible representations.