👉 The lambda fluid, also known as the lambda liquid or lambda viscous fluid, is a theoretical model describing a state of matter where particles exhibit both fluid-like and solid-like behavior simultaneously, but without the conventional viscosity or elasticity. This unique state arises from particles interacting in a highly ordered manner, forming a network that can flow like a liquid but also display elastic properties akin to solids. The lambda point, observed in certain systems like water and certain polymers at a specific temperature and pressure, marks the transition between these two states. This phenomenon is significant in understanding complex materials and their behavior under various conditions, offering insights into the fundamental interactions at play in condensed matter physics.