A crystal is a material structure of least entropy and most strength. Crystals have special properties, such as some having the ability to bend light, and others having the ability to flood themselves with an electric charge when compressed.

Resonance is achieved when a frequency of sound, light, or another oscillating force is equal or close to the natural frequency of a material. This causes the amplitude of oscillation in the material to be boosted.

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Photons | Sound waves | Time crystal | Electromagnetism | Ions | Ionic salts | Refraction | Piezoelectric | Pressure | Hooke's Law | Beer-Lambert Law | Amplitude | Frequency | LEDs | Diodes