Relativitetsfaktorn

Relativitetsfaktorn, often denoted by the Greek letter gamma (γ), is a crucial concept in Albert Einstein's theory of special relativity. It quantifies how certain physical properties of an object change when observed from a different frame of reference that is moving at a significant fraction of the speed of light. Specifically, it accounts for the effects of time dilation and length contraction.

The relativitetsfaktorn is defined by the equation γ = 1 / √(1 - v²/c²), where 'v' is the relative velocity between the two frames of reference and 'c' is the speed of light in a vacuum. As the relative velocity 'v' approaches the speed of light 'c', the value of the relativitetsfaktorn increases dramatically. If 'v' is much smaller than 'c', the factor is very close to 1, meaning relativistic effects are negligible, and classical Newtonian physics provides a sufficiently accurate description.

When an object moves at relativistic speeds, an observer in a stationary frame will perceive the object's clock as running slower (time dilation) and its length in the direction of motion as being shorter (length contraction). The relativitetsfaktorn is the multiplier by which these effects occur. For example, time experienced by the moving object is dilated by a factor of γ relative to the stationary observer. Similarly, the length of the moving object appears contracted by a factor of 1/γ. This factor is also fundamental in the relativistic definition of momentum and energy.