Welcome to the PHF team!

Hey well done Pmb! I knew since the beginning that you'd be of a great help for PHF.

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Isaac
If the problem is too hard just let the Universe solve it.

Welcome Pmb

Thanks everyone. It is an honor to be a helper.

I'm always looking for better ways to explain physics so I have a question for all of you. Someone recently made the assertion that if you give someone more than a simple yes or no answer to a simple question then the person asking the question is overwhelmed. I find that to be a silly assertion. Here is the example I used.

Suppose someone asks you the question "Does light have mass?" One person answers "No". I find that to be misleading. Here is how I wold answer it "A photon has zero rest mass, since it can't be at rest, non-zero relativistic mass since it has momentum, non-zero passive gravitational mass, since its effected by a gravitational field and non-zero active gravitational mass since it can generate a gravitational field."

Are any of you overwhelmed by that answer? I could have gotten more precise since "light" and "photon" are different things and the answer can be more complicated depending on the exact nature of the light.

Pmb, I find much more interesting a full answer rather than a "No" or "Yes". It is not overwhelming in my opinion if you give details, after all we're in a physics forum, not a general opinion one.

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Isaac
If the problem is too hard just let the Universe solve it.

Thanks for the response.

I do have to say that the people who say "Light has no mass" would certainly be confused by these lecture comments
http://www.pa.msu.edu/courses/2005fall/AST207/10-31.pdf

I've decided to make this my permanent forum-home so I'll be visiting here much more in the future. You guys have made visiting here a very positive experience.

Pete