"Biot-Savart equivalent" of Faraday's Law?

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Discussion Overview

The discussion revolves around the exploration of a potential "Biot-Savart equivalent" of Faraday's Law, examining the relationships between electric and magnetic fields as described by Maxwell's equations. Participants are considering theoretical formulations and implications of these laws in the context of changing magnetic fields and their effects on electric fields.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants propose that Ampere's Law can be derived from the Biot-Savart Law and draw parallels between Faraday's Law and Ampere's Law.
  • One participant questions how to construct the entire electric field vector due to a changing magnetic field without a specific equation.
  • Another participant argues that Maxwell's equations do not adequately describe the Biot-Savart Law or the changing electric field, suggesting the need for a new formulation.
  • There is a suggestion to consult external resources, such as Wikipedia or professors, for further insights on the topic.
  • One participant emphasizes the necessity of using the full Maxwell equations when dealing with time-dependent magnetic fields.
  • Another participant expresses interest in the Jefimenko equations as a solution for given charge-current distributions and questions the consistency of their proposed formula with these equations.

Areas of Agreement / Disagreement

Participants do not reach a consensus; multiple competing views remain regarding the formulation of an equivalent to Faraday's Law and the applicability of existing laws in this context.

Contextual Notes

Some limitations include the dependence on specific definitions and the unresolved nature of the proposed equations and their relationship to established laws.

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This is a repeat of this thread https://www.physicsforums.com/threads/biot-savart-version-of-maxwell-faraday-equation.855423/

That thread was dominated by one verbose poster. I am repeating this thread so as to hear the opinions of others.Ampere's Law can be derived from the Biot-Savart Law.
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Faraday's Law is similar to Ampere's Law.

Is there a "Biot-Savart equivalent" of Faraday's Law?

I imagine it might look something like this: (not taking into account Coulomb's Law)

\frac{d\vec{E}}{dV}=\frac{-\left(\frac{∂\vec{B}}{∂t}\right)×\vec{1_r}}{4\pi r^2}
 
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Without an equation like the one above, how can we construct the entire E-vector field due to a changing magnetic field?
 
Maxwell's equations include ##∇×B=\mu_0 J## and ##∇×E=-\frac{∂B}{∂t}##

##∇×B=\mu_0 J## cannot adequately describe the Biot-Savart Law, the same with ##∇×E=-\frac{∂B}{∂t}##, which is why I've conceived the above.
 
jedishrfu said:
It seems there's not much response here.
Also have you checked with your profs?
Yeah, but I don't think that this is a boring question.

Prof is asleep. No response.
The wiki doesn't have anything on this.

I thought of this question because of the parallel between E and M and I also want to construct the entire E-vector field due to a changing magnetic field
 
Try finding a prof who isn't asleep maybe an applied mathematics profs or one in EE.
 
Well, if the magnetic field is time dependent then also very likely the electric field is, and then you need (generally) the full Maxwell equations. So the Ampere law should be used as the full Ampere-Maxwell Law,
$$\vec{\nabla} \times \vec{B}-\frac{1}{c} \partial_t \vec{E}=\frac{1}{c} \vec{j}.$$
The Maxwell equations for given charge-current distributions are solved by the retarded propagator (aka Jefimenko equations):

https://en.wikipedia.org/wiki/Jefimenko's_equations
 
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vanhees71 said:
The Maxwell equations for given charge-current distributions are solved by the retarded propagator (aka Jefimenko equations):

https://en.wikipedia.org/wiki/Jefimenko's_equations

Ooh, thanks for bringing that to my attention. I had conceived Jefimenko's idea independently, now I know of the equations.

is the formula below (after taking into account Coulomb's Law) consistent with the Jefimenko equations?

\frac{d\vec{E}}{dV}=\frac{-\left(\frac{∂\vec{B}}{∂t}\right)×\vec{1_r}}{4\pi r^2}
 

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