Is There a Gauss' Law for Gravitation?

[aniketp]

hello,
I was wondering if there is an equivalent gauss' law for gravitation like:
\Phi=4\piG*M_enclosed
any help would be appreciated. Thank you.

 

[Doc Al]

Absolutely. See: "[URL law for gravity[/URL]

 

[aniketp]

thank you. but do magnetic fields have any such law? intuitively, i am inclined to say no,
because magnetic field lines can cross...but i would like a rigorous proof

 

[Doc Al]

but do magnetic fields have any such law? intuitively, i am inclined to say no,
because magnetic field lines can cross...but i would like a rigorous proof

Yes, there's a Gauss's law for magnetic fields--it's one of Maxwell's Equations. Since there are no magnetic monopoles, it is rather simple: http://en.wikipedia.org/wiki/Gauss%27_law_for_magnetism" .

Magnetic field lines can cross only where the field is zero.

 

[Defennder]

I'm curious as to why there isn't any magnetic monopoles. The freshman physics textbook I read for my intro physics course says that current theory (I think it was Serway) does predict the existence of magnetic monopoles.

 

[Phrak]

No one seems to have found any magnetic monopoles. By including magnetic charge and magnetic current terms in Maxwell's equations you postulate magnetic charge. It brings some (anti-) symmetry to the equations, but this is inconsistence with the magnetic potential.