- #1

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With the term "subject to length contraction" I mean that the length of the object parallel to its one- dimensional motion, would contract.

Many thanks

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- Thread starter Einstein's Cat
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- #1

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With the term "subject to length contraction" I mean that the length of the object parallel to its one- dimensional motion, would contract.

Many thanks

- #2

PAllen

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- #3

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I see; thank you for the corrections.

I'll give an analogy for what I mean by "along" and "through" a space.

Say there's a line along a y- axis and that this line is a one- dimensional space. A circle with two degrees of freedom can either travel "along" the space by travelling parallel to the line or "through" the space by travelling perpendicular to the line. In this case the line represents three dimensional space and the circle represents an object of 3+ dimensions.

Let's say there's an obsever, Bob, who's stationary. He sees a 3 dimensional object with velocity v and thus the length of the object parrallel to its one dimensional motion is contracted from his frame of reference. It travels "along" 3- dimensional space.

Next Bob sees an object of 3+ dimensions of the same velocity, v, that travels "through" 3- dimensional space. Would the length parallel to its one dimensional motion be contracted in Bob's frame of reference?

Hopefully this makes the question (more) valid!

- #4

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- #5

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So it may not have any physical significance but hypothetically would the length of the 3+ object be contracted?

Edit: crossed posts with the OP's clarification. I think the above answers the question.

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I would think that would depend on the rules of geometry obeyed by higher dimensional objects. Since we have no idea if there are more dimensions than the four we know, we don't know what rules they might obey. So, no idea.So it may not have any physical significance but hypothetically would the length of the 3+ object be contracted?

- #7

Mister T

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Please excuse any stupidity, but I'm under the impression that objects that travel "along" 3- dimensional" space (therefore the objects are three dimensional) with velocity v are subject to length contraction.

If the object is moving relative to an observer, then the observer will witness length contraction. But the contraction is only along the line of motion, not in the other two directions.

- #8

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Therefore as a 3+ dimensional object travels "through" 3D space there's no one dimensional motion and thus no length contraction; Is this correct?If the object is moving relative to an observer, then the observer will witness length contraction. But the contraction is only along the line of motion, not in the other two directions.

- #9

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We don't know because we don't know if more dimensions than just the four exist, so we don't know how they would behave if they did exist.Therefore as a 3+ dimensional object travels "through" 3D space there's no one dimensional motion and thus no length contraction; Is this correct?

- #10

Drakkith

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