Hi, I was just wondering if heisenbergs uncertainty principal is about position and velocity (or energy and time),.. then how come we can know that a photon travels at light speed (its velocity) exactly and also know that it hit some detector (its position).(adsbygoogle = window.adsbygoogle || []).push({});

If we know the velocity exactly then the light must be everywhere at the same time right?

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Heisenbergs Uncertainty for light

**Physics Forums | Science Articles, Homework Help, Discussion**