How Do Plane Waves Behave in Electromagnetic Theory?

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SUMMARY

This discussion focuses on the behavior of plane waves in electromagnetic theory, specifically the relationship between electric (E) and magnetic (B) fields as described by Maxwell's equations. It is established that a changing electric field generates a magnetic field and vice versa. However, the conversation highlights that longitudinal waves, such as those found in plasmas, can exist where the electric field propagates without an accompanying magnetic field, as long as the condition \(\vec k \times \vec E = 0\) is met. Visual resources and further reading materials were also shared to enhance understanding.

PREREQUISITES
  • Understanding of Maxwell's equations
  • Familiarity with electromagnetic wave propagation
  • Knowledge of longitudinal and transverse waves
  • Basic concepts of plasma physics
NEXT STEPS
  • Explore visualizations of electromagnetic waves using simulation tools like MATLAB or Python's Matplotlib
  • Study the implications of Maxwell's equations on wave behavior in different media
  • Research electron plasma waves and ion acoustic waves in plasma physics
  • Learn about the conditions for longitudinal wave propagation in various physical contexts
USEFUL FOR

This discussion is beneficial for physics students, educators, and researchers interested in electromagnetic theory, wave behavior, and plasma physics.

Ratzinger
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I would like to see some nice visualizations of plane waves. Has anyone a nice link or knows a book where to find such?

For EM waves the perpendicular E and B vector span a plane at each instant of time, right?

What if there would be only an electric field wave. Would there be also a planes, i.e. are there many electric field vectors aligned next to each other at each point in time?
 
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Maybe posting #6 in this thread will help:

https://www.physicsforums.com/showthread.php?p=533190

I don't think it's possible to have a wave of E without an accompanying wave of B. According to Maxwell's equations, a changing E field automatically produces a B field, and a changing B field automatically produces an E field.
 
Yes, it is possible to have an electric field wave with no magnetic field so long as \vec k \times \vec E = 0, i.e. the waves are longitudinal. Such will occur in plasmas (electron plasma waves, ion acoustic waves, etc.).
 
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Thanks for replying. I also found something.

http://www.cs.brown.edu/stc/outrea/greenhouse/nursery/physics/emwave.html

neat
 
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