The concept of time is complex and cannot be strictly defined, reflecting its nuanced nature in relation to physical phenomena. The assertion highlights the interplay between time and the speed at which signals travel, suggesting that our understanding of time is intrinsically linked to how quickly information can be conveyed through space.

This relationship between time and signal velocity emphasizes that the perception of time can vary based on the context of motion and measurement. Walter Isaacson's examination of Einstein in "Einstein: His Life and Universe" showcases these intricate connections, illustrating how revolutionary ideas shaped our understanding of time and its fundamental role in the universe.