👉 Perturbation refers to a change in structure or appearance of something due to a small change in its parameters. This can be caused by changes in temperature, humidity, atmospheric pressure, or other environmental factors that do not directly affect the physical properties of the material. For example, if you were to add water vapor to a dry towel, it would initially appear slightly damp and more slippery than before, but over time, the moisture would evaporate and the towel would become slightly drier. This is
