Imports
/- Copyright (c) 2025 Joseph Tooby-Smith. All rights reserved. Released under Apache 2.0 license as described in the file LICENSE. Authors: Joseph Tooby-Smith -/ module public import Physlib.Electromagnetism.Kinematics.ElectricField

The Magnetic Field

i. Overview

In 3-spatial dimensions from the electromagnetic potential we can define the magnetic field \vec B as (∇ ⨯ (A.vectorPotential t)) x. In this module we define this magnetic field from the electromagnetic potential.

In general dimensions we define the magnetic field matrix from the spatial components of the field strength matrix. This is an antisymmetric matrix.

ii. Key results

    ElectromagneticPotential.magneticField : The magnetic field from the electromagnetic potential in 3 spatial dimensions.

    ElectromagneticPotential.magneticFieldMatrix : The magnetic field matrix from the electromagnetic potential in general spatial dimensions.

    ElectromagneticPotential.time_deriv_magneticFieldMatrix : The time derivative of the magnetic field matrix in terms of the vector potential. (Aka Faraday's law).

iii. Table of contents

    A. The magnetic field

      A.1. Relation between the magnetic field and the field strength matrix

      A.2. Divergence of the magnetic field

    B. The field strength matrix in terms of the electric and magnetic fields

    C. Magnetic field matrix

      C.1. Antisymmetry of the magnetic field matrix

      C.2. Magnetic field in terms of the magnetic field matrix

      C.3. Magnetic field matrix in terms of vector potentials

      C.4. Smoothness of the magnetic field matrix

      C.5. Differentiablity of the magnetic field matrix

      C.6. Spatial derivative of the magnetic field matrix

      C.7. Temporal derivative of the magnetic field matrix

      C.8. curl of the magnetic field matrix

iv. References

@[expose] public sectionattribute [-simp] Fintype.sum_sum_typeattribute [-simp] Nat.succ_eq_add_one

A. The magnetic field

lemma magneticField_eq {c : SpeedOfLight} (A : ElectromagneticPotential) : A.magneticField c = fun t x => ( (A.vectorPotential c t)) x := rfl

A.1. Relation between the magnetic field and the field strength matrix

i:Fin 3c:SpeedOfLightA:ElectromagneticPotentialt:Timex:SpacehA:Differentiable (A.val 3)(fderiv (fun x => (vectorPotential c A t x).ofLp (i + 1)) x) (Space.basis (i + 2)) = (fderiv (fun y => A.val 3 ((toTimeAndSpace c).symm (t, y)) (Sum.inr (i + 1))) x) (Space.basis (i + 2))i:Fin 3c:SpeedOfLightA:ElectromagneticPotentialt:Timex:SpacehA:Differentiable (A.val 3)Differentiable fun y => A.val 3 ((toTimeAndSpace c).symm (t, y)) i:Fin 3c:SpeedOfLightA:ElectromagneticPotentialt:Timex:SpacehA:Differentiable (A.val 3)Differentiable fun y => A.val 3 ((toTimeAndSpace c).symm (t, y)) i:Fin 3c:SpeedOfLightA:ElectromagneticPotentialt:Timex:SpacehA:Differentiable (A.val 3)Differentiable fun y => A.val 3 ((toTimeAndSpace c).symm (t, y)) All goals completed! 🐙

A.2. Divergence of the magnetic field

c:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:TimeContDiff 2 (vectorPotential c A t) All goals completed! 🐙

A.4. The magnetic field on constructors

B. The field strength matrix in terms of the electric and magnetic fields

All goals completed! 🐙c:SpeedOfLightA:ElectromagneticPotentialx:SpaceTimehA:Differentiable (A.val 3)μ:Fin 1 Fin 3ν:Fin 1 Fin 3(A.fieldStrengthMatrix x) (μ, ν) = (A.fieldStrengthMatrix ((toTimeAndSpace c).symm (((toTimeAndSpace c) x).1, ((toTimeAndSpace c) x).2))) (μ, ν)c:SpeedOfLightA:ElectromagneticPotentialx:SpaceTimehA:Differentiable (A.val 3)μ:Fin 1 Fin 3ν:Fin 1 Fin 3Differentiable (A.val 3) c:SpeedOfLightA:ElectromagneticPotentialx:SpaceTimehA:Differentiable (A.val 3)μ:Fin 1 Fin 3ν:Fin 1 Fin 3Differentiable (A.val 3) All goals completed! 🐙

C. Magnetic field matrix

lemma magneticFieldMatrix_eq {c : SpeedOfLight} (A : ElectromagneticPotential d) : A.magneticFieldMatrix c = fun t x ij => A.fieldStrengthMatrix ((toTimeAndSpace c).symm (t, x)) (Sum.inr ij.1, Sum.inr ij.2) := rfllemma fieldStrengthMatrix_inr_inr_eq_magneticFieldMatrix {c : SpeedOfLight} (A : ElectromagneticPotential d) (x : SpaceTime d) (i j : Fin d) : A.fieldStrengthMatrix x (Sum.inr i, Sum.inr j) = A.magneticFieldMatrix c (x.time c) x.space (i, j) := d:c:SpeedOfLightA:ElectromagneticPotential dx:SpaceTime di:Fin dj:Fin d(A.fieldStrengthMatrix x) (Sum.inr i, Sum.inr j) = magneticFieldMatrix c A ((time c) x) (space x) (i, j) All goals completed! 🐙

C.1. Antisymmetry of the magnetic field matrix

lemma magneticFieldMatrix_antisymm {c : SpeedOfLight} (A : ElectromagneticPotential d) (t : Time) (x : Space d) (i j : Fin d) : A.magneticFieldMatrix c t x (i, j) = - A.magneticFieldMatrix c t x (j, i) := fieldStrengthMatrix_antisymm A ((toTimeAndSpace c).symm (t, x)) (Sum.inr i) (Sum.inr j)@[simp] lemma magneticFieldMatrix_diag_eq_zero {c : SpeedOfLight} (A : ElectromagneticPotential d) (t : Time) (x : Space d) (i : Fin d) : A.magneticFieldMatrix c t x (i, i) = 0 := fieldStrengthMatrix_diag_eq_zero A ((toTimeAndSpace c).symm (t, x)) (Sum.inr i)

C.2. Magnetic field in terms of the magnetic field matrix

lemma magneticField_eq_magneticFieldMatrix {c : SpeedOfLight} (A : ElectromagneticPotential) (hA : Differentiable A) : A.magneticField c = fun t x => WithLp.toLp 2 fun i => - A.magneticFieldMatrix c t x ((i+1), (i+2)) := c:SpeedOfLightA:ElectromagneticPotentialhA:Differentiable (A.val 3)magneticField c A = fun t x => WithLp.toLp 2 fun i => -magneticFieldMatrix c A t x (i + 1, i + 2) c:SpeedOfLightA:ElectromagneticPotentialhA:Differentiable (A.val 3)t:Timex:Spacei✝:Fin 3(magneticField c A t x).ofLp i✝ = (WithLp.toLp 2 fun i => -magneticFieldMatrix c A t x (i + 1, i + 2)).ofLp i✝ All goals completed! 🐙x:Spacei:Fin 3c:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Time(curl ((fun t x => WithLp.toLp 2 fun i => -magneticFieldMatrix c A t x (i + 1, i + 2)) t) x).ofLp i = j, Space.deriv j (fun x => magneticFieldMatrix c A t x (j, i)) x x:Spacei:Fin 3c:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Time-(fderiv (fun y => magneticFieldMatrix c A t y (i + 2 + 1, i + 2 + 2)) x) (Space.basis (i + 1)) + (fderiv (fun y => magneticFieldMatrix c A t y (i + 1 + 1, i + 1 + 2)) x) (Space.basis (i + 2)) = (fderiv (fun x => magneticFieldMatrix c A t x (0, i)) x) (Space.basis 0) + (fderiv (fun x => magneticFieldMatrix c A t x (1, i)) x) (Space.basis 1) + (fderiv (fun x => magneticFieldMatrix c A t x (2, i)) x) (Space.basis 2) x:Spacec:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Time-(fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 0, + 2 + 1, (fun i => i) 0, + 2 + 2)) x) (Space.basis ((fun i => i) 0, + 1)) + (fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 0, + 1 + 1, (fun i => i) 0, + 1 + 2)) x) (Space.basis ((fun i => i) 0, + 2)) = (fderiv (fun x => magneticFieldMatrix c A t x (0, (fun i => i) 0, )) x) (Space.basis 0) + (fderiv (fun x => magneticFieldMatrix c A t x (1, (fun i => i) 0, )) x) (Space.basis 1) + (fderiv (fun x => magneticFieldMatrix c A t x (2, (fun i => i) 0, )) x) (Space.basis 2)x:Spacec:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Time-(fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 1, + 2 + 1, (fun i => i) 1, + 2 + 2)) x) (Space.basis ((fun i => i) 1, + 1)) + (fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 1, + 1 + 1, (fun i => i) 1, + 1 + 2)) x) (Space.basis ((fun i => i) 1, + 2)) = (fderiv (fun x => magneticFieldMatrix c A t x (0, (fun i => i) 1, )) x) (Space.basis 0) + (fderiv (fun x => magneticFieldMatrix c A t x (1, (fun i => i) 1, )) x) (Space.basis 1) + (fderiv (fun x => magneticFieldMatrix c A t x (2, (fun i => i) 1, )) x) (Space.basis 2)x:Spacec:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Time-(fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 2, + 2 + 1, (fun i => i) 2, + 2 + 2)) x) (Space.basis ((fun i => i) 2, + 1)) + (fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 2, + 1 + 1, (fun i => i) 2, + 1 + 2)) x) (Space.basis ((fun i => i) 2, + 2)) = (fderiv (fun x => magneticFieldMatrix c A t x (0, (fun i => i) 2, )) x) (Space.basis 0) + (fderiv (fun x => magneticFieldMatrix c A t x (1, (fun i => i) 2, )) x) (Space.basis 1) + (fderiv (fun x => magneticFieldMatrix c A t x (2, (fun i => i) 2, )) x) (Space.basis 2) x:Spacec:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Time-(fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 0, + 2 + 1, (fun i => i) 0, + 2 + 2)) x) (Space.basis ((fun i => i) 0, + 1)) + (fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 0, + 1 + 1, (fun i => i) 0, + 1 + 2)) x) (Space.basis ((fun i => i) 0, + 2)) = (fderiv (fun x => magneticFieldMatrix c A t x (0, (fun i => i) 0, )) x) (Space.basis 0) + (fderiv (fun x => magneticFieldMatrix c A t x (1, (fun i => i) 0, )) x) (Space.basis 1) + (fderiv (fun x => magneticFieldMatrix c A t x (2, (fun i => i) 0, )) x) (Space.basis 2)x:Spacec:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Time-(fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 1, + 2 + 1, (fun i => i) 1, + 2 + 2)) x) (Space.basis ((fun i => i) 1, + 1)) + (fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 1, + 1 + 1, (fun i => i) 1, + 1 + 2)) x) (Space.basis ((fun i => i) 1, + 2)) = (fderiv (fun x => magneticFieldMatrix c A t x (0, (fun i => i) 1, )) x) (Space.basis 0) + (fderiv (fun x => magneticFieldMatrix c A t x (1, (fun i => i) 1, )) x) (Space.basis 1) + (fderiv (fun x => magneticFieldMatrix c A t x (2, (fun i => i) 1, )) x) (Space.basis 2)x:Spacec:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Time-(fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 2, + 2 + 1, (fun i => i) 2, + 2 + 2)) x) (Space.basis ((fun i => i) 2, + 1)) + (fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 2, + 1 + 1, (fun i => i) 2, + 1 + 2)) x) (Space.basis ((fun i => i) 2, + 2)) = (fderiv (fun x => magneticFieldMatrix c A t x (0, (fun i => i) 2, )) x) (Space.basis 0) + (fderiv (fun x => magneticFieldMatrix c A t x (1, (fun i => i) 2, )) x) (Space.basis 1) + (fderiv (fun x => magneticFieldMatrix c A t x (2, (fun i => i) 2, )) x) (Space.basis 2) x:Spacec:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Time-(fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 2, + 2 + 1, (fun i => i) 2, + 2 + 2)) x) (Space.basis ((fun i => i) 2, + 1)) + (fderiv (fun y => magneticFieldMatrix c A t y ((fun i => i) 2, + 1 + 1, (fun i => i) 2, + 1 + 2)) x) (Space.basis ((fun i => i) 2, + 2)) = (fderiv (fun x => magneticFieldMatrix c A t x (0, (fun i => i) 2, )) x) (Space.basis 0) + (fderiv (fun x => magneticFieldMatrix c A t x (1, (fun i => i) 2, )) x) (Space.basis 1) + (fderiv (fun x => magneticFieldMatrix c A t x (2, (fun i => i) 2, )) x) (Space.basis 2) x:Spacec:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Time-(fderiv (fun y => magneticFieldMatrix c A t y (2, 0)) x) (Space.basis 0) + (fderiv (fun y => magneticFieldMatrix c A t y (1, 2)) x) (Space.basis 1) = (fderiv (fun x => magneticFieldMatrix c A t x (0, 2)) x) (Space.basis 0) + (fderiv (fun y => magneticFieldMatrix c A t y (1, 2)) x) (Space.basis 1) conv_lhs => x✝:Spacec:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Timex:Space| magneticFieldMatrix c A t x (2, 0) x✝:Spacec:SpeedOfLightA:ElectromagneticPotentialhA:ContDiff 2 (A.val 3)t:Timex:Space| -magneticFieldMatrix c A t x (0, 2) All goals completed! 🐙

C.3. Magnetic field matrix in terms of vector potentials

d:c:SpeedOfLightA:ElectromagneticPotential dhA:Differentiable A.valt:Timex:Space di:Fin dj:Fin dSpace.deriv i (fun x => A.val ((toTimeAndSpace c).symm (t, x)) (Sum.inr j)) x = Space.deriv i (fun x => ((timeSlice c) (fun x => WithLp.toLp 2 fun i => A.val x (Sum.inr i)) t x).ofLp j) xd:c:SpeedOfLightA:ElectromagneticPotential dhA:Differentiable A.valt:Timex:Space di:Fin dj:Fin dDifferentiable fun y => A.val ((toTimeAndSpace c).symm (t, y)) d:c:SpeedOfLightA:ElectromagneticPotential dhA:Differentiable A.valt:Timex:Space di:Fin dj:Fin dDifferentiable fun y => A.val ((toTimeAndSpace c).symm (t, y)) All goals completed! 🐙

C.4. Smoothness of the magnetic field matrix

lemma magneticFieldMatrix_contDiff {n} {c : SpeedOfLight} (A : ElectromagneticPotential d) (hA : ContDiff (n + 1) A) (ij) : ContDiff n (fun t x => A.magneticFieldMatrix c t x ij) := d:n:WithTop ℕ∞c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff (n + 1) A.valij:Fin d × Fin dContDiff n fun t x => magneticFieldMatrix c A t x ij All goals completed! 🐙lemma magneticFieldMatrix_space_contDiff {n} {c : SpeedOfLight} (A : ElectromagneticPotential d) (hA : ContDiff (n + 1) A) (t : Time) (ij) : ContDiff n (fun x => A.magneticFieldMatrix c t x ij) := d:n:WithTop ℕ∞c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff (n + 1) A.valt:Timeij:Fin d × Fin dContDiff n fun x => magneticFieldMatrix c A t x ij exact (magneticFieldMatrix_contDiff A hA ij).comp (f := fun x => (t, x)) (d:n:WithTop ℕ∞c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff (n + 1) A.valt:Timeij:Fin d × Fin dContDiff n fun x => (t, x) All goals completed! 🐙)lemma magneticFieldMatrix_time_contDiff {n} {c : SpeedOfLight} (A : ElectromagneticPotential d) (hA : ContDiff (n + 1) A) (x : Space d) (ij) : ContDiff n (fun t => A.magneticFieldMatrix c t x ij) := d:n:WithTop ℕ∞c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff (n + 1) A.valx:Space dij:Fin d × Fin dContDiff n fun t => magneticFieldMatrix c A t x ij exact (magneticFieldMatrix_contDiff A hA ij).comp (f := fun t => (t, x)) (d:n:WithTop ℕ∞c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff (n + 1) A.valx:Space dij:Fin d × Fin dContDiff n fun t => (t, x) All goals completed! 🐙)

C.5. Differentiablity of the magnetic field matrix

lemma magneticFieldMatrix_differentiable {c : SpeedOfLight} (A : ElectromagneticPotential d) (hA : ContDiff 2 A) (ij) : Differentiable (fun t x => A.magneticFieldMatrix c t x ij) := d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valij:Fin d × Fin dDifferentiable fun t x => magneticFieldMatrix c A t x ij All goals completed! 🐙lemma magneticFieldMatrix_differentiable_space {c : SpeedOfLight} (A : ElectromagneticPotential d) (hA : ContDiff 2 A) (t : Time) (ij) : Differentiable (fun x => A.magneticFieldMatrix c t x ij) := d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timeij:Fin d × Fin dDifferentiable fun x => magneticFieldMatrix c A t x ij exact (magneticFieldMatrix_differentiable A hA ij).comp (f := fun x => (t, x)) (d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timeij:Fin d × Fin dDifferentiable fun x => (t, x) All goals completed! 🐙)lemma magneticFieldMatrix_differentiable_time {c : SpeedOfLight} (A : ElectromagneticPotential d) (hA : ContDiff 2 A) (x : Space d) (ij) : Differentiable (fun t => A.magneticFieldMatrix c t x ij) := d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valx:Space dij:Fin d × Fin dDifferentiable fun t => magneticFieldMatrix c A t x ij exact (magneticFieldMatrix_differentiable A hA ij).comp (f := fun t => (t, x)) (d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valx:Space dij:Fin d × Fin dDifferentiable fun t => (t, x) All goals completed! 🐙)

C.6. Spatial derivative of the magnetic field matrix

d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin d(fun i_1 => Space.deriv j (Space.deriv k fun x => (vectorPotential c A t x).ofLp i) i_1 - Space.deriv i (Space.deriv k fun x => (vectorPotential c A t x).ofLp j) i_1) x = (fun i_1 => Space.deriv j (Space.deriv i fun x => (vectorPotential c A t x).ofLp k) i_1 - Space.deriv i (Space.deriv k fun x => (vectorPotential c A t x).ofLp j) i_1) x - (fun i_1 => Space.deriv j (Space.deriv i fun x => (vectorPotential c A t x).ofLp k) i_1 - Space.deriv j (Space.deriv k fun x => (vectorPotential c A t x).ofLp i) i_1) xd:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv i fun x => (vectorPotential c A t x).ofLp k)d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv k fun x => (vectorPotential c A t x).ofLp i)d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv j fun x => (vectorPotential c A t x).ofLp k)d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv k fun x => (vectorPotential c A t x).ofLp j)d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv j fun x => (vectorPotential c A t x).ofLp i)d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv i fun x => (vectorPotential c A t x).ofLp j) d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv i fun x => (vectorPotential c A t x).ofLp k)d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv k fun x => (vectorPotential c A t x).ofLp i)d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv j fun x => (vectorPotential c A t x).ofLp k)d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv k fun x => (vectorPotential c A t x).ofLp j)d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv j fun x => (vectorPotential c A t x).ofLp i)d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv i fun x => (vectorPotential c A t x).ofLp j) all_goals d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dDifferentiable (Space.deriv i fun x => (vectorPotential c A t x).ofLp j) d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dk:Fin dContDiff 2 fun x => (vectorPotential c A t x).ofLp j All goals completed! 🐙

C.7. Temporal derivative of the magnetic field matrix

d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin d:ContDiff 2 (scalarPotential c A t)hd1: (k : Fin d), DifferentiableAt (fun x => -(electricField c A t x).ofLp k) xhd2: (k : Fin d), DifferentiableAt (Space.deriv k (scalarPotential c A t)) x-Space.deriv j (fun x => (electricField c A t x).ofLp i) x - Space.deriv i (Space.deriv j (scalarPotential c A t)) x - (-Space.deriv i (fun x => (electricField c A t x).ofLp j) x - Space.deriv i (Space.deriv j (scalarPotential c A t)) x) = Space.deriv i (fun x => (electricField c A t x).ofLp j) x - Space.deriv j (fun x => (electricField c A t x).ofLp i) x All goals completed! 🐙d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 3 A.valt:Timex✝:Space di:Fin dj:Fin dx:Space dDifferentiable fun t' => electricField c A t' x All goals completed! 🐙) | d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 3 A.valt:Timex:Space di:Fin dj:Fin dDifferentiableAt (fun t => Space.deriv j (fun x => (electricField c A t x).ofLp i) x) t | (d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 3 A.valt:Timex:Space di:Fin dj:Fin dDifferentiable fun t => Space.deriv j (fun x => (electricField c A t x).ofLp i) x d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 3 A.valt:Timex:Space di:Fin dj:Fin dContDiff 2 fun t x => (electricField c A t x).ofLp i All goals completed! 🐙)

C.8. curl of the magnetic field matrix

d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dSpace.deriv j (fun x => magneticFieldMatrix c A t x (j, i)) x = Space.deriv j (fun y => (A.fieldStrengthMatrix ((toTimeAndSpace c).symm (((toTimeAndSpace c) ((toTimeAndSpace c).symm (t, x))).1, y))) (Sum.inr j, Sum.inr i)) ((toTimeAndSpace c) ((toTimeAndSpace c).symm (t, x))).2d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dDifferentiable fun x => (A.fieldStrengthMatrix x) (Sum.inr j, Sum.inr i) d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dSpace.deriv j (fun x => magneticFieldMatrix c A t x (j, i)) x = Space.deriv j (fun y => (A.fieldStrengthMatrix ((toTimeAndSpace c).symm (t, y))) (Sum.inr j, Sum.inr i)) xd:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dDifferentiable fun x => (A.fieldStrengthMatrix x) (Sum.inr j, Sum.inr i) d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dDifferentiable fun x => (A.fieldStrengthMatrix x) (Sum.inr j, Sum.inr i) d:c:SpeedOfLightA:ElectromagneticPotential dhA:ContDiff 2 A.valt:Timex:Space di:Fin dj:Fin dDifferentiable fun x => (A.fieldStrengthMatrix x) (Sum.inr j, Sum.inr i) All goals completed! 🐙