Insights Introducing Relativity on Rotated Graph Paper: A Graphical Motivation

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The discussion centers on the concept of illustrating relativity through the use of rotated graph paper, emphasizing a non-algebraic motivating argument for understanding time dilation and length contraction. The author references a previous work that established the equality of light-clock diamond areas and provides algebraic proof in a related article. The motivation for the graphical approach is aimed at enhancing comprehension of special relativity concepts. The omitted non-algebraic argument from the earlier draft is now included in the new piece, enriching the educational framework. This approach seeks to make the principles of relativity more accessible to learners.
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(based on https://www.physicsforums.com/threads/teaching-sr-without-simultaneity.1011051/post-6588952 and https://physics.stackexchange.com/a/689291/148184 )

In my earlier Insight Spacetime Diagrams of Light Clocks,
I stated without proof that the areas of all light-clock diamonds are equal.
In my article,Relativity on Rotated Graph Paper, Am. J. Phys. 84, 344 (2016)
I provided algebraic proof.

In the penultimate draft, I had a non-algebraic motivating argument (which also motivates time dilation and length contraction)
that had to be left out because the article was already too long.
This argument now appears in Introducing relativity on rotated graph paper...

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