Yu Huang

A sheet of paper weighs almost nothing, but stack a hundred sheets and you get a noticeable pile. That's roughly what scientists did with a material that excels at converting one color of light into another, but only when it's just one atom thick. A single layer is like a single sheet: it works beautifully, but it's too thin to produce much light.

A grand symphony orchestra plays, but each group of instruments follows its own score without hearing the others. The violins carry the melody of the heart, the cellos the rhythm of the liver, and the woodwinds the pulse of the brain. It sounds disjointed, even though each part is flawless on its own.