Creative Thinking

How the brightest minds in science – from Einstein to Da Vinci – revealed the nature of light

Unravel the mysteries of light as we delve into the minds of scientific luminaries like Einstein and Da Vinci. Their groundbreaking insights have shaped our understanding of this fundamental force, illuminating our world in ways previously unimaginable.

at is light?

Light behaves like a wave in certain conditions and as a particle in others

Pythagoras, Euclid, and Ptolemy believed that light moved in straight lines
The eye emitted visual rays, like feelers, which touched the object and thereby created the sensation of sight in the mind
This ancient idea of light and sight was taught in the West in various forms until the 12th century AD
Ibn al-Haytham rejected this view
Leonardo da Vinci proposed that the eye is a camera obscura, into which light rays penetrate via a small aperture and create an inverted image of an exterior scene on the retina

Particle or Wave?

By 1770, two theories of light, apparently incompatible, were in competition

An undulatory theory: light transmitted as waves
Christiaan Huygens in 1678 and published in 1690
Light waves spread in all directions from a light source, and were detected by their creation of vibrations in the retina.
In contrast, Isaac Newton, who began his optical experiments in 1666, favored a corpuscular theory of light as particles
The real test of the two theories was experiment
When light strikes the surface of water and passes through it, the angles of incidence and refraction differ
Refraction was a more decisive test
Finally, there was diffraction, a phenomenon first noticed in the mid-17th century by Francesco Grimaldi in a room through a larger aperture, then passed through a sharper aperture than the one in front of it, and was diffracted into the outer edge of the room.