L. Kohn's Theorem is a result in the field of mathematical analysis, particularly in the study of partial differential equations. It provides conditions under which certain types of solutions exist for specific boundary value problems. This theorem is significant in understanding the behavior of solutions in complex domains. The theorem is named after L. Kohn, a mathematician known for his contributions to analysis and differential equations. It has applications in various areas, including quantum mechanics and fluid dynamics, where understanding the properties of solutions is crucial for modeling physical phenomena.