3 ms·

Phase velocity vs group velocity. Yes, thank you. Why did it take me so many words? :)

• mirkules 15y ago
  I'm glad that it did take you so many words. I remember reading about this a while back, but could never remember what it was called, or why the light particles actually didn't break the speed barrier. I really appreciate your laymen explanation, and now, thanks to you parent, also know what the effect is called.
  • Florin_Andrei 15y ago
    Think of the wagon wheels, as seen in a western movie, turning back, or moving at bizarre speeds in either direction. It's not a perfect analogy, but it's a related phenomenon.
    • 0x12 15y ago
      That's called aliasing.
• Florin_Andrei 15y ago
  Well, you gave the layman's explanation. Not everyone is well versed in these specific terms.