# Angular momentum

russ_watters
Mentor
I tried to split/merge a couple of threads here...hope I didn't do too much damage.

I am sorry to upset you, but I found an experiment that shows the currently accepted definition of angular momentum r x p is incorrect. That is why I was interested in knowing who defined angular momentum as r x p and why. Unfortunately, I have been unable to do it, so far at least. Anyway, I understand that, in physics, the experimental truth has the last word, and that should not be suppressed.
What is this experiment in which the definition of angular momentum fails? You can't keep making vague allusions to some nebulous "experiment" in which one of the fundamental conservation laws of physics breaks down.

reilly
The standard theory of angular momentum is widely used -- in Classical mechanics, planetary orbits, and E&M multipole expansions, and very widely used in QM -- to the point that there are textbooks on QM Angular Momentum -- Edmonds, for example. So far R x P has never been found wrong , in thousands of applications -- unless ... MRW is not, repeat not angular momentum. Rather it is is linear momentum in the direction of the circular motion. The angular mometum is perpendicular to the plane of motion. Further, the standard formula for angular momentum follows from the requirments of rotational invariance, as many textbooks will show.
What's the problem? Give us some proof.

Regards,
Reilly Atkinson

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I smell crackpot physics!

he scored 35 points according to the index!!

http://math.ucr.edu/home/baez/crackpot.html

Honestly, either tell us what your thought experiment is and let the experts straighten your thoughts or get a good classical mechanics book and read (or even search in Wikipedia).

Could you please describe the experiment to us so that we can help you clear any confusions?
I will as soon as I can.

russ_watters
Mentor
No point in keeping this open to speculate about something we can't read and isn't appropriate for the forum anyway...