What would happen if you fire an electron at 299,792,456 m/s from a gun moving at 2m/s?
Originally asked on Quora
Since this is not technically possible there are multiple factors that you can choose to negate.
If you choose to negate that an object with mass, when moving the speed of light becomes a frozen state until the end of time, then the electron will simply leave the gun and will be 299,792,454 meters away from the gun by the end of the first second as opposed to 299,792,456 meters away if fired from a stationary gun.
An analogous example of this would be the earth and us. At the equator earth spins at 466 m/s. That however does not mean we are moving 466m/s on the earth. It simply means that we are moving 466m/s through space, taller people moving a little faster. She we run west at 1 m/s, we are partially counteracting the Earth’s spin and are instead moving through space at 465 m/s. It matters not the speed the gun is going at the time it goes off. Because that instant is technically paused, thus time cannot be of an object. The only thing that matters is where the gun and electron are located at the end of that second.
If you choose to only negate that objects with mass cannot move at the speed of light then the electron would experience near infinite time dilation (since it is not moving at the precise speed of light, a factor which would not be of great important to objects with great mass but are for objects with little mass per special relativity). Would almost immediately catch up to the electron, but would be unable to interact with it thus would pass straight through it. Assuming the gun continues moving at 2m/s for all of time and does not biodegradable near the end of time the electron would have moved 299,792,456 meters from its original locations and may surpass the gun depending on how far away the end of time is when the electron is fired. However, as per special relativity, the electron would only experience a second in all those years meaning that the electron would continue traveling at that speed almost forever (assuming the electron does not experience resistance and does not lose momentum) even when the gun is swallowed up by the end of time. This demonstrates why time does not end - because of particles such as a photon that travel at the speed of light and would not experience times end for being almost unaffected by time itself.
