Physics
Time Dilation
Quick fact
At 99% the speed of light, a traveler would age just 1 year for every 7 years that pass on Earth.
Why this is interesting
Imagine two twins: one travels near light speed while the other stays on Earth. When they reunite, one will be younger than the other—this is time dilation in action.
Read the full explanation
Understanding Time Dilation
Time dilation occurs when an object moves at high speeds relative to another. From the perspective of a stationary observer, time appears to slow down for the moving object. This effect becomes more pronounced as the speed approaches that of light.
A deeper explanation
Time dilation is a consequence of Einstein's theory of special relativity. It arises because the speed of light remains constant in all reference frames. As an object moves faster, its time slows relative to a stationary observer, making time itself dependent on motion and not absolute.