Can the B field be obtained from the magnetic potential using matrix inversion?

AI Thread Summary
The discussion revolves around deriving the B field from the magnetic potential A field using the curl operation, expressed as B = ∇ × A. There are challenges in matrix inversion related to this conversion, as the corresponding matrix may not be invertible. The conversation shifts to obtaining the A field from a given B field, which depends on the specific problem being addressed. Reference to Green's functions in electromagnetic theory is suggested for further understanding. The importance of verifying calculations by checking the curl is also noted.
sinyud
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How do you get the B field from the magnetic potential?
I tried converting the curl into matrix format, but the corresponding matrix can't be inverted.
 
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It's just the curl of the vector potential:

\vec B = \nabla \times \vec A

I'm not sure what you're tyring to do with it.
 
I got it backward. How do you the A field from a B field?
 
Oh! Well in that case ... it depends on what problem you're trying to solve. Check with a good E&M book for some discussion on Green's functions. That might help. It's been a while since I worked with that so I'd have to review it myself.
 
\vec{A} = \pm \frac{1}{2} \vec{B} \times \vec{r} if memory serves me correctly...
 
Thanks, Dr. T! Sinyud could easily check that by calculating the curl.
 
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