🧄Tensor Analysis of the Magnetic Stress Tensor

The analysis of the magnetic field tensor ( FijF_{i j} ) demonstrates the power of tensor notation in physics, showing how its inherent anti-symmetry ( Fij=FjiF_{i j}=-F_{j i} ) leads directly to the symmetry of its square, FijFjkF_{i j} F_{j k}, a necessary condition for a physical stress tensor. The derivation relies heavily on the Levi-Civita identity to compute the tensor product, yielding the key result FijFjk=B2δikBiBkF_{i j} F_{j k}=B^2 \delta_{i k}-B_i B_k, which links the fundamental magnetic field tensor to the standard vector dyadic product. Finally, by expressing the scalar field energy ( B2B^2 ) as a trace of the tensor product ( B2=12FikFkiB^2=\frac{1}{2} F_{i k} F_{k i} ), the entire Maxwell stress tensor ( TikT_{i k} ) is converted into a form defined exclusively by the magnetic field tensor FijF_{i j}, ensuring mathematical consistency and demonstrating the elegance of field-based tensor formalisms.

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