Brick a broke

Q: How does one throw a brick through a window without making any noise?

A: Seems there are foul deeds afoot! However, like a nuclear arms manufacturer or the tabacco industry, it's not my place to presuppose the intent of my customers -- it's entirely possible you have a legitimate reason for wanting to throw a brick through a window.

It could be for a hollywood stunt, for instance. Or perhaps you really need to have a brick inside your house, but for some innocent reason don't have easy access to the interior of the house. Maybe the brick forgot its keys and you're just helping it out.

Either way, very sensitive of you to not want to disturb the neighbours with the raucous sound of shattering glass!

One needs only a basic knowledge of the physics of sound in order to answer your question. Sound is caused by tiny particles vibrating and disturbing the particles on either side of it. Eventually some of these distrurbed particles knock against our eardrums, which our brain processes as sound.

However, there is a phenomenon called noise cancellation. You may have heard of this in reference to noise-cancelling headphones. This is the process of generating a sound that has the inverse wave of another sound. At the midpoint of two identical sounds, the movements in the particles cancel each other out, and the human ear can no longer detect that any sound was issued -- eventhough it's really two identical sounds being issued simultaneously from an equal distance!

So all you need to do is convince a friend (who, ideally has identical size weight and proportions to you) to throw an identical brick through an identical window, in exactly the same manner, at exactly the same moment, and at exactly the same distance from the location at which you would like to keep the breaking glass inaudible.

Simple, isn't it?

Sure, it may mean losing two windows instead of one, but your neighbours will have a solid night's sleep.