The discussion explores the existence of an equation similar to the Young-Laplace equation that relates pressure differences to the shape of surfaces in elastic solids, particularly at solid-gas and solid-solid interfaces. It highlights the complexity of solid-solid interfaces due to the regular crystalline structure of true solids, which limits their deformability compared to fluids. Additionally, it notes that in thermodynamics, polyphase solids like alloys require an extra term in the First Law to account for surface energy at grain boundaries. The conversation suggests a need for further clarification on the specific requirements or applications of such an equation. Overall, the topic emphasizes the unique challenges in modeling pressure effects in solid materials.