the.com/light
the universe's speed limit, and it never once got a ticket
means Light is the visible radiant energy that lets us see, or anything bright, pale, or not heavy depending on which sense you mean.
from Two different words wearing the same coat. The 'brightness' sense comes from Old English 'lēoht,' from a Proto-Germanic root tied to a very old Indo-European word for shining, the same ancient family that gave Latin 'lux' and Greek 'leukos' (white). The 'not heavy' sense comes from a separate Old English word, 'lēoht' (or 'līht'), traced to an Indo-European root meaning easy or nimble, a cousin of Latin 'levis' (light in weight, source of 'levity'). English simply let the two settle into one spelling.
- speed
- 299,792,458 meters per second, exactly, by definition
- age
- sunlight is 8 minutes old when it hits you
- weightless
- photons have zero mass yet carry momentum
- identity crisis
- behaves as both wave and particle
- no time
- from light's view, no time passes at all
sun — star at center of solar system, 93 million miles from earth, provides all natural light for our planet
incandescent bulb — invented by thomas edison in 1879, produces light by heating a filament to glowing temperatures
firefly bioluminescence — photinus pyralis produces light through chemical reaction in abdomen, common in eastern north america
laser — first ruby laser built by theodor maiman in 1960, produces coherent monochromatic light beam