Silence is often defined as the absence of sound, but it's important to clarify that it is not the absence of all sound waves or vibrations. In a typical environment, true absolute silence is challenging to achieve because there are usually ambient sounds present, such as the hum of electronics, the sound of air conditioning, or even the soft background noise of nature.
However, when we refer to silence, we generally mean a perceived absence of significant or noticeable sound. This absence of sound can be understood as the absence of distinct and discernible vibrations or pressure waves that our ears can detect. Sound waves are essentially variations in air pressure that propagate as vibrations through a medium, such as air, water, or solid objects. We perceive these vibrations as sound when they reach our ears and are processed by our auditory system.
In complete silence, there are no discernible sound waves or vibrations present that would stimulate our auditory system. Consequently, our perception is that of silence. However, it's worth noting that our ears are capable of detecting extremely low levels of sound, and in truly quiet environments, we might still perceive faint sounds, such as the internal sounds of our own body or the blood flow.
In summary, silence can be understood as the absence of sound waves or vibrations that are detectable and distinguishable by our ears, resulting in the perception of quietness or lack of audible sound.