If a variable Electric field creates a variable magnetic field and VICE VERSA (according to Maxwell's equations), then why don't we enter a loop where E vector and B vector keep creating one another until they reach infinite magnitudes?
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Because it does not work that way. Have you had a look at any solutions to Maxwell's equations? – Cryo Jul 09 '19 at 15:22
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3by the way, your feeling is based on the fact that an infinite sum is necesseraly infinite. Which is not true: $\sum_n \frac{1}[n^2} = \pi^2/6$ for example. – StarBucK Jul 09 '19 at 15:32
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More often than not, verbose descriptions of physics are not precise enough to be relied upon to base such new arguments in them that which would rely on the precise details of the description. – Jul 09 '19 at 16:56
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It is a misunderstanding that electric and magnetic fields generate each other. They do not. – my2cts Jul 09 '19 at 18:19
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Care to elaborate, @my2cts? I'm down with the idea that the statement is loose, but there are Maxwell's equations and an array of practical devices that work off this basic idea. Like motors and generators. – Brick Jul 09 '19 at 19:12
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Relevant Q & A here: Do the electric and magnetic components of an electromagnetic wave really generate each other? – Hal Hollis Jul 09 '19 at 20:38
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Infinite? Doesn't re-creation pass through $0$? And why would the fields exceed their previous maximum? – Cinaed Simson Jul 11 '19 at 20:05
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@StarBuck:But $\sum_n n^{2} =n(n+1)(2n+1)/6$ does approach $\infty$ as $n\rightarrow \infty$. – Cinaed Simson Jul 11 '19 at 20:23
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Ah, this was actually the great insight of Maxwell. What you are referring to is electromagnetic waves (i.e. light). These waves are just the electric and magnetic field continuously generating each other. Unlike what you may intuit though, looking at the actual mathematical solutions that yield such behavior shows that the magnitude of the fields never actually grow but either stay the same (e.g. plane waves) or shrink (e.g. spherical waves). This can easily be seen by Poynting's theorem which shows that Maxwell's equations conserve energy or, more specifically, the quantity $\frac{\epsilon_0E^2}{2}+\frac{B^2}{2\mu_0}$ is conserved in vacuums.
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This can not happen if only by energy conservation. The Maxwell equations may seem to indicate otherwise but electric and magnetic fields do not generate one another. They are mutually dependent quantities and it is this fact that is expressed in two of the four equations.
my2cts
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The fields are vectors with (signed) direction. In a wave, the $\mathbf{B}$ field "creates" $\mathbf{E}$ field components, but they are, at some times at least, opposite to the currently present $\mathbf{E}$ field and therefore reduce the total field. And vice versa. This manifests via the relative minus sign between Faraday's law $$ \nabla \times \mathbf{E} = -\frac{\partial \mathbf{B}}{\partial t}$$ and Ampere's law $$ \nabla \times \mathbf{B} = \frac{\partial \mathbf{E}}{\partial t}$$ (shown here in units where $c=1$ and in vacuum).
Brick
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Because according to Maxwell's equations there is no infinite growth of energy but periodic overflow of energy(which is remains constant) from the magnetic field to the electric field and right back.
Leiba Goldstein
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