Domain | Electromagnetism | Acoustics | ||
Alignment | Transverse | Longitudinal | Transverse | Longitudinal |
Permittivities |
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Permeabilities |
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Currents |
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Continuity equations |
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Fields | , | , | , | , |
Adjoint fields |
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Quanta of fields | Transverse photon | Longitudinal photon | Transverse phonon | Longitudinal phonon |
Motion equations (in d’Alembert form) |
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Gauges |
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Free wave equations |
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Shadow wave equations |
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Energy flows |
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Energy densities |
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Quantized charges |
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