Zeitstreckung

Zeitstreckung, also known as time dilation, is a phenomenon predicted by Albert Einstein's theory of relativity. It describes the difference in elapsed time measured by two observers. This difference arises due to either a difference in their relative velocity or a difference in their gravitational potential.

In special relativity, time dilation occurs because the speed of light is constant for all observers. If two observers are moving relative to each other, each observer will perceive the other's clock as running slower. The faster the relative speed, the greater the time dilation. This effect becomes significant only at speeds approaching the speed of light.

In general relativity, time dilation is caused by gravity. Clocks in stronger gravitational fields run slower than clocks in weaker gravitational fields. This means that time passes more slowly for an observer closer to a massive object, such as a planet or a black hole, compared to an observer farther away.

Experimental evidence for time dilation includes observations of muons reaching Earth's surface despite their short lifespan, and the precise functioning of GPS satellites, which must account for both special and general relativistic time dilation effects to maintain accuracy. The concept of time dilation challenges our intuitive understanding of time as absolute and universal, demonstrating instead its relative and observer-dependent nature.