The Pros And Cons Of Pole Contracting

Length contraction is the phenomenon in which a rapidly moving object appears to approach zero length as it accelerates. Though the object’s length appears unchanged in its own reference frame, an observer will see it contract at a rapidly increasing rate the closer it gets to the speed of light. The object’s length in an observer frame of reference is equal to its length at rest divided by the Lorentz factor. Due to this, an object’s length will asymptotically approach zero the closer its squared velocity gets to the speed of light. (Interestingly, this phenomenon provides further evidence that no massive object can travel at the speed of light. When it is moving at exactly c, the length becomes zero regardless of starting length. Since this

Under normal circumstances, this pole would be too long to fit inside the barn. Then, accelerate the pole rapidly towards the barn at speeds that are at least a significant fraction of the speed of light (Obviously, this could never be actually done, as the energy required would be several times our current energy output, but as a purely theoretical experiment it still holds water). Assuming length contraction is true, the inertial perspective of the barn would observe the pole contracting. And, since in our thought experiment the pole can reach any arbitrary fraction of c, the pole will inevitably contract to the point that it can fit inside the barn. Then, the doors of the barn could be closed and the pole decelerated to zero velocity. Through this method, any pole could fit within a barn of any

In this mind experiment, we conjecture that a bug is living at the bottom of a deep hole in the wall, and some person is attempting to squash it by pushing a rivet into the hole at high speeds. However, the rivet is not long enough to squash the bug at the bottom of the hole. As the paradox goes, the bug at the bottom of the hole should never have to worry about being squashed, because the rivet is not long enough at rest and any velocity increase would cause it only to contract further, making the bug even safer. However, at the same time, the person should never have to worry about not crushing the bug. This is because, from the rivet’s perspective, it is actually the wall that is accelerating towards the rivet. This means that the wall will be the one that is experiencing length contraction. Thus, if the person slams the rivet fast enough, the wall (and thus the hole) will grow short enough for the rivet to reach the bottom of the hole and kill the bug. We are then left with a seemingly irresolvable Schrodinger’s Cat-type paradox, where the bug appears to be both alive and dead at the same