Divergenceless vector function - can we draw component by componet conclusion?

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A divergenceless vector function, represented as ∇ · A = 0, does not imply that each component's partial derivative is zero. The conclusion that ∂Ai/∂xi = ∂Aj/∂xj = ∂Ak/∂xk = 0 is only valid if the vector field A is constant throughout the space. In general, divergencelessness indicates a relationship between the components but does not necessitate their individual vanishing. Therefore, the assertion is false unless A is a constant vector field. Understanding this distinction is crucial in vector calculus and physics applications.
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divergenceless vector function - can we draw "component by componet" conclusion?

Homework Statement



Is this true or false?

\nabla \bullet {\bf{A}} = \frac{{\partial {A_i}}}{{\partial {x_i}}} + \frac{{\partial {A_j}}}{{\partial {x_j}}} + \frac{{\partial {A_k}}}{{\partial {x_k}}} = 0{\rm{ }} \to {\rm{ }}\frac{{\partial {A_i}}}{{\partial {x_i}}} = \frac{{\partial {A_j}}}{{\partial {x_j}}} = \frac{{\partial {A_k}}}{{\partial {x_k}}} = 0

...in which the arrow says "implies that".

Thanks!
 
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No, of course not, unless the components of A in the normal basis are numbers independent of the point (x,y,z) in which the vector is defined. In other words, A is a constant vector field.
 

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