### Why does length shrink and mass increase at relativistic speeds?

Length Contraction at Relativistic Speeds Imagine you're aboard a spacecraft, accelerating to a speed that approaches the speed of light. As you traverse the vast cosmic expanse, you notice something peculiar: the distances between celestial landmarks seem to shorten or contract. This phenomenon is known as length contraction. The reason behind length contraction lies in Einstein's theory of special relativity. According to this groundbreaking theory, space and time are intertwined in what's known as spacetime. As an object moves closer to the speed of light, its movement through spacetime changes. From the perspective of an observer at rest, the object's length in the direction of motion appears to shrink. This isn't a physical compression of the object itself. Instead, it's a perceptual effect arising from the alteration of spacetime due to high velocities. Essentially, the faster an object moves, the more its passage through spacetime becomes skewed, leading