Is there such a thing as stagnate sound energy within the body? This post will focus on the physics of sound mechanical vibration to show that the energy from a sound wave cannot collect or store within the body. Mechanical vibration follows Newton’s Laws of Motion where molecules collide with each other as it travels away from the source. The sound source will oscillate in a certain way to compress nearby molecules and push them away from the source. A Newton’s cradle shows the Laws of Motion in action as the ball on one end strikes the next ball and the inertia carries through to the remaining balls. We do not see a wave like the ocean because the balls are constrained, but we do notice the final ball swinging away and back to the cradle to start the sequence in the other direction.
Newton’s first law states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force. We call this phenomenon “inertia”, and it means that once a molecule is in motion it will remain in motion until some external force will stop the motion. Usually, the main factors are friction, reflection, and refraction (bending). In the Newton’s Cradle, friction occurs each time the balls strike each other and the continuous motion slows down as it loses inertia. Once the inertia is gone, the vibration wave no longer exists as explained in the second law of motion showing how the speed of an object changes when it is subjected to an external force. The law defines a force to be equal to a change in momentum. This means the both inertia and momentum are both influenced by the external environment. Friction is the biggest reason why the movement stops.
What I’m about to tell you is at the core of the misunderstanding associated with sound being absorbed into the body’s tissue. What does it mean to absorb something? It certainly sounds like the ability to store energy by absorbing it. However, that’s not what absorption means in the physics governing mechanical vibration. If you do a quick Google search for Absorption (acoustic), Wikipedia states, “Acoustic absorption refers to the process by which a material, structure, or object takes in sound energy when sound waves are encountered, as opposed to reflecting the energy. Part of the absorbed energy is transformed into heat and part is transmitted through the absorbing body. The energy transformed into heat is said to have been ‘lost’.”
This is why we call it “Absorption Loss” in our acoustic loss equations. It’s lost because the mechanical energy is converted into heat which falls under the laws of physics for electro-magnetic energy. In this type of energy, molecules do not collide and transmit the same way. Heat energy radiates outward in a different way. This is why the sound energy is lost. We might also think that heat is stored, but what you are feeling in a heated tissue is the radiated heat moving away from the friction source. This still doesn’t mean that the energy (in whatever form) is being stored in the tissue.
There are many concepts within sound healing with a focus on releasing stored energy within the body. If physics does not support these theories, then what are the mechanisms responsible for results experienced in certain methods and techniques? This is the subject for a very good discussion to dig into the details of how sound vibration affects the human body. What are your thoughts on this subject given the information presented in this post?