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Anonymous Poster #1

# Longitudinal Electromagnetic Wave

10/08/2016 5:38 AM

Text book always teaching about transverse EM wave. Could you explain in detail and give example of longitudinal Electromagnetic wave.

How come the electric and magnetic field are not perpendicular in logitudinal EM wave.

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#1

### Re: Longitudinal Electromagnetic wave

10/08/2016 6:58 AM
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#2

### Re: Longitudinal Electromagnetic wave

10/08/2016 9:37 AM

Electromagnetic waves are traverse, i.e., the electric field vector and magnetic field vectors are perpendicular to each other and to the direction of propagation (the Pointing vector).

Longitudinal electromagnetic waves don't exist. A longitudinal wave is not a solution to Maxwell's equations. However, there is another set of solutions that result in twisted waves.

http://frankrayal.com/2012/05/20/twisted-waves-a-new-dimension-in-wireless-communication/

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#3

### Re: Longitudinal Electromagnetic Wave

10/09/2016 2:31 PM

The longitudinal wave is not electro-magnetic. It is magneto-dielectric. The text books don't teach magneto-dielectrics, even though much of the work by Steinmetz is based on it. Steinmetz literally wrote "the book" that is the basis of modern electronics but most of his work is left out of the texts.

If you want to study longitudinal waves, study Steinmetz.

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#6
In reply to #3

### Re: Longitudinal Electromagnetic Wave

10/12/2016 10:12 AM

FYI, a paper about Maxwell's equations expressed as quaternion form:

https://arxiv.org/pdf/math-ph/0307038v1.pdf

I haven't had a chance to study this.

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#4

### Re: Longitudinal Electromagnetic Wave

10/10/2016 11:22 AM

Longitudinal electromagnetic waves go north-south, while latitudinal electromagnetic waves go east-west. Transverse electromagnetic waves is what happens when a regular electromagnetic wave takes to wearing high heels and a corset.

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Anonymous Poster #2
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In reply to #4

### Re: Longitudinal Electromagnetic Wave

10/10/2016 1:01 PM

Pretty bad but I got a good laugh out of it.

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