Maxwell's equations in relativistic physics

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SUMMARY

Maxwell's equations in differential form are valid in special relativity, while the integral form presents a paradox due to the finite speed of light, c. Specifically, the equation \(\nabla \times \mathbf{E} = -\frac{\partial \mathbf{B}} {\partial t}\) implies that an alternating magnetic field generates an electric field circulation instantaneously, which contradicts the relativistic constraint that information cannot travel faster than light. This discussion highlights the need to reconcile this apparent violation through classical electrodynamics principles, particularly in scenarios involving propagation delays in electromagnetic fields.

PREREQUISITES
  • Understanding of Maxwell's equations in both differential and integral forms
  • Familiarity with special relativity and the concept of information propagation speed
  • Basic knowledge of classical electrodynamics
  • Ability to interpret mathematical notation used in physics
NEXT STEPS
  • Study the implications of special relativity on electromagnetic theory
  • Explore classical electrodynamics solutions to paradoxes in Maxwell's equations
  • Investigate the role of propagation delays in electromagnetic field interactions
  • Examine advanced topics in electromagnetic theory, such as gauge invariance
USEFUL FOR

Physics students, educators, and researchers interested in the intersection of electromagnetism and relativity, particularly those tackling advanced concepts in classical electrodynamics.

elivil
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Homework Statement


It is often said that Maxwell's equations in differential form hold in special relativity while Maxwell's equations in integral form don't hold. Consider one of equations:
\nabla \times \mathbf{E} = -\frac{\partial \mathbf{B}} {\partial t}
\oint_{\partial S} \mathbf{E} \cdot \mathrm{d}\mathbf{l} = - \frac {1} {c} \frac {d} {dt} \int \mathbf {B} \cdot \mathrm{d} \mathbf {S}

Consider the integral form. It means that if one has an alternating magnetic field, then in any contour around this field circulation of electrical field immediately appears . If one takes a very long tube and at one end of the tube somehow generates an alternating magnetic field then in contour (radius R) around the tube circulation of electric field immediately appears. But in relativistic case it can't appear immediately because it will take time t=\frac {R} {c} for news about alternating magnetic field to come to this contour. So here we have the violation of this equation in relativistic case.
Still this 'paradox' can be solved in terms of classical electrodynamics. But how?


Homework Equations


\nabla \times \mathbf{E} = -\frac{\partial \mathbf{B}} {\partial t}
\oint_{\partial S} \mathbf{E} \cdot \mathrm{d}\mathbf{l} = - \frac {1} {c} \frac {d} {dt} \int \mathbf {B} \cdot \mathrm{d} \mathbf {S}


The Attempt at a Solution


Maybe it takes time for propagation of alternating magnetic field from one end of the tube to the point A where cross-section of the tube by the plane of the contour is. So in fact it takes equal time to propagate inside the tube and outside the tube so it appears as simultaneously arising magnetic field at point A in the tube and electric field in the contour around the tube. But I'm not quite sure.
 
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This should be moved to the advanced physics forum. I'd take a stab at it, but my Maxwell is rusty, and I might hurt myself with it.
 

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