Do Massless Particles Travel at Light Speed?

AI Thread Summary
Massless particles, such as photons, travel at the speed of light, a fact supported by observational evidence. The discussion emphasizes the fundamental nature of massless particles in physics, highlighting that their behavior aligns with established scientific principles. The conversation briefly touches on the complexities of particle movement and the evolution of physics since Newton's time. Overall, the consensus is clear that massless particles inherently move at light speed. This understanding is crucial for deeper explorations in modern physics.
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do all mass less particles travel at the speed of light?
 
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Yes.
 
Doc Al said:
Yes.

Why?
 
Why?

PHRAK...Stop teasing Doc Al!

Best answer I know: that's what we observe.
 
But I was just getting started...

First we have "particles" and they're "moving", and this is supposed to be physics 200 years after Newton.
 
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