More About Light in Cosmos
A brief recap of the properties of light that we have encountered so far in Cosmos.
- The speed of light through vacuum is nature’s speed limit.
- Light travels in straight lines.
- The speed of light depends on the medium.
- Visible light is composed of seven primary colors.
- Energy of light waves depends on their wavelength.
- Our eyes are sensitive to a small band of electromagnetic radiation.
These properties were hiding in plain sight but it took centuries and the work of many individuals to unravel these properties. Lots of imagination and hard work went into getting nature to reveal its code to us. You may ask, how does this concern me? Why should I care? It does because the entire edifice of modern life, from your hand held device to your camera phone uses this knowledge. To paraphrase Newton, each of us can see farther because we are standing on the shoulders of giant. Technological progress is possible because of research in the pure sciences. Unfortunately funding for science is getting shortchanged these days in the name of fiscal prudence, see for example, sequestration.
Still to come:
- Light can demonstrate both wave-like and particle like phenomena.
- Light waves are transverse electromagnetic waves.
- Light can travel through vacuum
The last property has been taken for granted but never been elaborated upon by Neil De Grasse Tyson while narrating Cosmos. There is a great story lurking behind that fact, I hope he tells it in one the upcoming episodes.