Undergrad Rindler Coordinates & Quadrants: Resolving an Issue

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Rindler coordinates are said to cover the first quadrant of Minkowski space, but this interpretation raises questions due to the definition of a quadrant as one quarter of an Euclidean plane. In one spatial dimension, Rindler coordinates actually represent a region bounded by two 45° lines, which complicates their classification as a quadrant. The discussion highlights that, in the context of spacetime diagrams, the two lightlike lines divide Minkowski spacetime into four regions, each referred to as a quadrant. This suggests that the Rindler wedge can indeed be considered one-quarter of the plane if the perspective is adjusted. Understanding this concept requires a shift in viewpoint, which is a common challenge for those new to relativity.
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Im reading a text where the author says that the Rindler coordinates cover the first quadrant of Minkowski space and thus can be used as coordinates there. He is considering only 1 spatial dimension.

I learned in high school that a quadrant is one quarter of an Euclidean plane. I looked up definitions on the web and the term may also refer to a 90° arc lengh of a circle.

But in the case of Rindler coordinates, considering only 1 space dimension, its clear that they cover only a part of Minkowski space that is bounded by two 45° lines, and this is not in agreement with the definitions of a quadrant.

On the other hand, I have so little knowledge about Relativity, so is this term used differently in Relativity?
 
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kent davidge said:
Im reading a text where the author says that the Rindler coordinates cover the first quadrant of Minkowski space and thus can be used as coordinates there. He is considering only 1 spatial dimension.

I learned in high school that a quadrant is one quarter of an Euclidean plane. I looked up for definitions on the web and the term may also refer to a 90° arc lengh of a circle.

But in the case of Rindler coordinates, considering only 1 space dimension, its clear that they cover only a part of Minkowski space that is bounded by two 45° lines, and this is not in agreement with the definitions of a quadrant.

On a spacetime diagram, the two lightlike lines ("lines at 45°") partition Minkowski spacetime (for one spatial dimension) into four regions. In this context, each of these regions is called a quadrant.
 
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kent davidge said:
I learned in high school that a quadrant is one quarter of an Euclidean plane.
The Rindler wedge IS one-quarter of the plane. If it bothers you that the edges of the quadrant aren't vertical and horizontal, you can always turn your sheet of paper a quarter-turn counterclockwise.
 
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Nugatory said:
The Rindler wedge IS one-quarter of the plane. If it bothers you that the edges of the quadrant aren't vertical and horizontal, you can always turn your sheet of paper a quarter-turn counterclockwise.
Oh I had actually considered this as a possibility but discarded later.
 
kent davidge said:
Oh I had actually considered this as a possibility but discarded later.
I should have said one-eighth of a turn:smile: and seriously, kidding aside, one of the early challenges for someone learning relativity is to break themselves of the habit of privileging their own viewpoint.
 
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