On Built on Facts, Matt Springer writes that "there's really no such thing as a purely continuous monochromatic light wave" and "any pulse of light that lasts a finite amount of time will actually contain a range of frequencies." Pass this pulse of light through a medium such as glass, which "can have a different refractive index for each frequency," and some very weird things start to happen. On Life at the SETI Institute, Dr. Lori Fenton explains her study of "aeolian geomorphology - how wind shapes a planetary surface." As it does on Earth, weather makes wave patterns in the dunes of Venus, Mars, and Saturn's moon Titan, leaving a record of the meteorological forces at play. On Uncertain Principles, Chad Orzel takes a step back from wave-particle duality. Researchers have observed wave interference in molecules that "contain up to 430 atoms, and are several nanometers across, making them by far the largest objects anybody has ever seen displaying wave behavior." This brings the "quantum-classical boundary" a little closer to the human scale. But for now, we still behave a lot like particles.
- A Weird Refractive Index on Built on Facts
- Sand Seas of the Solar System on Life at the SETI Institute
- Wave Nature Gets Bigger: "Quantum interference of large organic molecules" on Uncertain Principles
Of course Fourier theory tells us this. A pure spike contains all frequencies and an infinite wave train contains only one.
(actually the two ends of the spectrum are just the manifestation in the time and frequency domains of the same thing.