Längenkontraktionen

Längenkontraktionen, also known as length contraction, is a phenomenon in special relativity where the length of an object moving relative to an observer is measured to be shorter along the direction of motion than its proper length. Proper length is the length of the object when measured in its own rest frame. This effect is only noticeable at speeds approaching the speed of light.

The formula for length contraction is L = L₀√(1 - v²/c²), where L is the contracted length, L₀ is the proper length, v is the relative velocity between the observer and the object, and c is the speed of light. As the velocity v approaches c, the term v²/c² approaches 1, making the square root term approach 0. This results in L becoming significantly smaller than L₀.

Length contraction is a consequence of the postulates of special relativity, particularly the constancy of the speed of light for all inertial observers. It means that measurements of length are not absolute but depend on the relative motion of the observer. It's important to note that length contraction only affects the dimension parallel to the direction of motion; dimensions perpendicular to the motion are unaffected.

While counterintuitive from a classical physics perspective, length contraction has been experimentally verified. For example, it plays a role in understanding the behavior of muons created in the upper atmosphere. Their short lifespan would prevent them from reaching the Earth's surface at their rest-frame speed, but due to length contraction from the perspective of the muons, the distance to the surface is shorter, allowing them to reach us.