- #1
Bucky
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I've been reading up on these three recently, and wondered if anyone could confirm what I think they do. I'm not 100% I understand these.
del [tex](\bigtriangleup)[/tex], when applied to a scalar, creates a vector with that scalar as each of the XYZ values. eg
[tex]\bigtriangleup . x = (x,x,x)[/tex]
[tex]\bigtriangleup . 3 = (3,3,3)[/tex]
divergence is applied to a vector, and sums the components of the vector into a scalar. eg
[tex]\bigtriangleup . (x,y,z) = x+y+z [/tex]
[tex]\bigtriangleup . (1,2,3) = 1+2+3 = 6 [/tex]
finally, laplacian. This is the one I'm not as sure about. It's applied to a scalar I think?
[tex]\bigtriangleup ^2 = \bigtriangleup(\bigtriangleup) [/tex]
[tex]\bigtriangleup ^2 . x = \bigtriangleup(\bigtriangleup . x) [/tex]
[tex]= \bigtriangleup((x,x,x)) [/tex]
[tex] = 3x [/tex]
That doesn't seem right (I think I'm meant to end up with a vector). Can laplacian be broken up like that or does it have a special rule?
del [tex](\bigtriangleup)[/tex], when applied to a scalar, creates a vector with that scalar as each of the XYZ values. eg
[tex]\bigtriangleup . x = (x,x,x)[/tex]
[tex]\bigtriangleup . 3 = (3,3,3)[/tex]
divergence is applied to a vector, and sums the components of the vector into a scalar. eg
[tex]\bigtriangleup . (x,y,z) = x+y+z [/tex]
[tex]\bigtriangleup . (1,2,3) = 1+2+3 = 6 [/tex]
finally, laplacian. This is the one I'm not as sure about. It's applied to a scalar I think?
[tex]\bigtriangleup ^2 = \bigtriangleup(\bigtriangleup) [/tex]
[tex]\bigtriangleup ^2 . x = \bigtriangleup(\bigtriangleup . x) [/tex]
[tex]= \bigtriangleup((x,x,x)) [/tex]
[tex] = 3x [/tex]
That doesn't seem right (I think I'm meant to end up with a vector). Can laplacian be broken up like that or does it have a special rule?