I was wondering whether a relativistic torpedo which is a futuristic cannonball measuring 1m in diameter could fit a small circular cracks on the surface of an energy shield with a diameter 10% smaller. Note that any contact with the energy shield would cause the torpedo to detonate prematurely! So I am wondering could the torpedo moving at fractional speed of light pass through the gap due to length contraction or I should write romance instead?
thou shall not pass!
Length contraction happens in the direction of motion, not isotropically.
If your bullet move such that it has a Lorentz factor of 0.1, that will apply only to the direction of the motion. Since the hole diameter will likely be transverse to that, the projectile won't pass.
I'm building on L.Dutch's answer, which I up voted
The problem here is that length contraction is one-dimensional along the vector of motion. That means that even if your torpedo contracts all the way to zero length, you still have a disk with a 1 meter diameter. This doesn't help you. No matter the orientation, you're trying to push a 1 meter object through a less-than-1-meter opening.
What you need is something that contracts in two dimensions! That way the torpedo would narrow and fit through the opening.
The only problem is that there's no science-based way to do that, that we know of.
I'll throw a question out to our Celestial Mechanics. I thought length contraction was an optical thing — something that was seen by the observer but was NOT an actual shortening of the physical object. Unfortunately, someone inside the torpedo using a measuring stick to measure the length of the torpedo would always measure a meter in length because either the physical contraction didn't occur or the stick is contracted along with the torpedo. So... physical contraction or observed optical contraction? Kinda curious.