The ladder paradox (or barn-pole paradox) is a thought experiment in special relativity.

This is illustrated in the ladder paradox, a thought experiment which uses the example of a ladder moving at high speed through a garage.

For examples see the Ladder paradox or Bell's spaceship paradox.

For example, special relativity has traditionally yielded two common paradoxes: the twin paradox and the ladder paradox.

Ladder paradox (special relativity)

Other known paradoxes are the Ladder paradox and Bell's spaceship paradox, which also can simply be solved by consideration of the relativity of simultaneity.

The dimensions (e.g., length) of an object as measured by one observer may be smaller than the results of measurements of the same object made by another observer (e.g., the ladder paradox involves a long ladder traveling near the speed of light and being contained within a smaller garage).