IN such elementary text-books on geometrical optics as I have consulted it has always seemed to me that the writers have found a difficulty in presenting a precise direct proof of the theorem that ...

Sunlight may be the bright, warming glow that heats and powers the Earth, but it's so much more than that. If you pass sunlight through a prism, you can see how it's actually composed of all the ...

Metamaterials with a refractive index of zero exhibit physical properties such as infinite phase velocity and wavelength. However, there is no way to implement these materials on a photonic chip, ...

Newton’s experiment remains almost insultingly simple. Sunlight, a darkened room, a glass prism. The conclusion was unavoidable. Colour belonged to light itself. The prism merely made it visible.