Soft Matter: The Science of Squishy Materials

Be it in their appearances or applications, soft matter or materials such as toothpastes, shampoos, lotions, sand, liquid detergents, milk, ice cream, and mayonnaise are different. Despite their apparent differences, they are all very similar in one regard – they can behave as rigid solids or flowing liquids depending on the external forces acting upon them. However, sand on a beach behaves like a solid and can support our weight when we walk on it. Take some of that sand in your palm and separate your fingers. The sand will flow right through under gravity, just like a liquid. Toothpaste stays in its tube till the time you squeeze it onto your toothbrush. Further, that little squeeze you applied was sufficient to convert the solid-like paste into a more liquid-like consistency.