Discovering the Meaning of a Plane Equation in 4D | Homework Equations

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Adding a fourth variable to a plane equation in 4D can be represented as Ax + By + Cz + Dk + E = 0. This equation does not represent a conventional shape, making visualization challenging. If the fourth dimension is interpreted as time, it could describe a moving plane, such as a plane wavefront. Additionally, the fourth variable may indicate the relative distance of the plane from a specific location. Understanding these concepts helps clarify the nature of planes in higher dimensions.
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Homework Statement



If you add a fourth variable to a plane and wrote the entire plane equation as a scalar equation, what would that equation represent?

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I'm guessing the scalar equation would look something like Ax + By + Cz + Dk + E = 0

The Attempt at a Solution



I was thinking that it can't represent a shape. I can't visualize it.
Then another thought - what would a plane in 4D look like? What IS 4D?

I'm not sure what the above equation would represent in terms of planes.
 
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Hi DespicableMe! :wink:
DespicableMe said:
I'm guessing the scalar equation would look something like Ax + By + Cz + Dk + E = 0

Then another thought - what would a plane in 4D look like? What IS 4D?

Yes, that's the right equation.

If the fourth dimension is time, that represents the equation of a moving plane, for example a plane wavefront. :smile:
 
tiny-tim said:
Hi DespicableMe! :wink:


Yes, that's the right equation.

If the fourth dimension is time, that represents the equation of a moving plane, for example a plane wavefront. :smile:

I also read somewhere that a fourth varible in a plane equation would express the relative distance of the (projection?) plane from a certain location.

What do you think of this? :redface:
 
Ah, that's the constant in a 3D equation …

for example x + y + z + D = 0 is a plane whose distance from the origin is 2D/√3 :wink:
 
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