Is an Electromagnetic Wave Truly 2D or 3D in Nature?

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Discussion Overview

The discussion revolves around whether an electromagnetic (EM) wave is fundamentally 2-dimensional or 3-dimensional in nature. Participants explore various models and interpretations of EM waves, including the implications of viewing them as spirals or helical structures versus traditional sinusoidal representations.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation

Main Points Raised

  • One participant suggests that an EM wave might be a spiraling particle, proposing that the "up-and-down" motion observed is a side view of a helical structure.
  • This participant argues that doubling the amplitude of a wave quadruples the energy, drawing parallels to the area of a circle and suggesting a circular cross-section for the wave.
  • Another participant asserts that EM waves are inherently three-dimensional, consisting of oscillating electric and magnetic field vectors, and challenges the idea of spiraling motion by stating that photons move in straight lines unless acted upon by a force.
  • A participant questions the validity of rejecting a spiral model based on the existence of a wave model, suggesting that observed phenomena can support alternative theories.
  • Another reply emphasizes that the standard sine wave representation is a vector field and not a path, indicating a misunderstanding of the figure's implications.

Areas of Agreement / Disagreement

Participants express competing views on the nature of EM waves, with no consensus reached on whether they are 2-dimensional or 3-dimensional. Disagreements arise regarding the validity of spiral models versus traditional wave interpretations.

Contextual Notes

Some participants highlight limitations in understanding the mechanics of EM waves, particularly regarding the forces required for circular motion and the interpretation of vector fields versus paths.

Futobingoro
Perhaps this has already been brought up, but is an electromagnetic wave 2-dimensional or 3-dimensional?

The current "up-and-down" concept does not have me convinced. If you look at a standard spring, you can see that it is a spiral/helix. You can also see that the side of the spring resembles a sine/cosine wave. So is an energy "wave" actually just a spiralling particle acting as a photon and appears to be an "up-and-down" wave only when viewed from the side?

If true, this would explain at least two phenomena:

1. When the amplitude of a "wave" is doubled the energy is quadrupled. In the formula for area of a circle (what would be the frontal cross-section of a spiral/helix), if one doubles the radius of the circle from 1cm to 2cm he goes from pi*cm^2 to 4pi*cm^2. Clearly, the so-called two dimensional wave acts as a circle when its amplitude is altered.

2. The side-view of EM radiation shows the standard sine wave and the path of the wave. The wave has the fastest vertical motion near the x-axis and slow vertical motion near the top and bottom.
This would lead one to believe that the particle is traveling forward and backward in space relative to the side view, characteristic of spiral motion.

It is much like a ferris wheel. If you arrange yourself so that you are in-line with the wheel, the vertical speed of the cars is evident. The cars have the highest vertical motion right at 0 degrees on the wheel. Once they near the top, their vertical speed is negligable. This is proven by the fact that at only 30 degrees, the sine measure is already at .5 radii. So if the motion of the particle on display screens exhibits slower speed at the crests and troughs of the sine wave, then there must be circular motion.

If the wave is as we know it now, the particle would remain at a constant velocity on the display screen, completing a 45-->135 degree segment in the same time as a -45-->+45 degree segment.

There are some interesting implications if this is true.

-The particle would always be traveling in the same direction, only around a helix.
-Is frequency determined by the angle of the particle in relation to the helix?
-Or its velocity...
-Or both?
-Is there an attracting body which holds the photon together?
-If the photon itself is traveling at the speed of light relative to the surroundings, then what is the velocity of the particle relative to the surroundings. (vector creating a small, but important, amount of forward velocity)
 
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An EM wave is a three dimensional object since it exists in three dimensions (or 4D if we consider special relativity).

It is an electric field vector and a magnetic field vector which oscillate about 0 sinusoidally at a fixed time period. That time period determines frequency.

Photons do not spiral because that would require a force towards the center of the spiralling (all circular motion requires a force towards the centre of the circle). Basically the photon moves in a straight line (or is likely to on macroscopic systems) because there is nothing to stop it. Macroscopically, photons do not spiral, although there is a small probability that they do.

Your question is confused. Remember, unless we measure where it goes at every point in a path, we don't know where it goes.
 
How can there be insufficient information to develop a spiral model if there is enough information to develop a wave model?

If we can not directly determine the activity in an EM photon, we can draw conclusions based upon observed phenomena.

This is just like the current belief in the structure in an atom.

I presented two phenomena which support my theory when I opened this thread.
 
I presented two phenomena which support my theory when I opened this thread.

And masudr presented a killer reason to reject your theory. There is no force that would make the wave go around in a circle. The point is that we know the mechanics of electromagnetism, we know how the electric and magnetic forces work and interact. Your theory is completely wrong.
 
Futobingoro said:
2. The side-view of EM radiation shows the standard sine wave and the path of the wave. The wave has the fastest vertical motion near the x-axis and slow vertical motion near the top and bottom.
This would lead one to believe that the particle is traveling forward and backward in space relative to the side view, characteristic of spiral motion.
This is a common misunderstanding of the standard figure. But that figure does not represent a path. It represents a vector field. Nice figures and animations that try to explain better are shown here:
http://www.cs.brown.edu/stc/outrea/greenhouse/nursery/physics/emwave.html
 
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