Jump to content
  • entries
  • comments
  • views

We will never go the speed of light



According to Einstein, nothing can move faster than the speed of light (which is exactly 299,792,458 m/s in a vacuum). However this hasn't stopped people from trying to think of clever ways to move something faster than this cosmic speed limit. It has been claimed that by shining a laser on the surface of the moon from earth and moving the laser quickly, the beam moves across the surface at faster than the speed of light, which is partially true. What is actually happening is that photons traveling at the speed of light are hitting the moon's surface in quick succession to form an imaginary spot that moves at faster than the speed of light, so nothing actually moves faster than light. A similar idea involves applying torque to a very long (in the magnitude of 500,000 km) rigid pole that pivots around one end, the idea being that the other end of the pole will move at faster than the speed of light. Unfortunately this is impossible since forces cannot move through materials at faster than the speed of sound and at that distance it is more than likely that all of the energy applied in the form of torque would be lost as heat in the process of the atoms in the material hitting each other in order to move your force through the object. (A related idea involves pushing one end of a light-year long pole in hopes that the other end would react instantaneously but this faces the same problems as the previous theory.) Finally, an idea similar to applying torque to a long pole is creating a spacecraft that spins with high rpm and torque and extends very long arms of something like carbon nano tubes to a very long length so that eventually the ends of the arms move the speed of light. The problem with this is that even with something as strong as carbon nano tubes, the required thickness of the arms would be literally impossible to make; and even with an impossibly strong material the electromagnetic force that hold the material together relies on the transmission of photons which only move at the speed of light.

*I did not come up with this on my own, I am just paraphrasing a Veritasium video which can be seen below.


Recommended Comments

There are no comments to display.

Add a comment...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...