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The only difficulty with the Minkowski diagram is that you have to forget Euclidean geometry entirely when interpreting it. The "length" is given by the Minkowski fundamental form rather than the Euclidean one, i.e., by the metric of space-time increments defined asminkowski diagram is beautiful once i understand how it slides. And I have become accustomed to picturing time as a sort of 'spatial' dimension that moves through the 3rd dimension even before I picked up this book, and yet this book still confused me

$$\mathrm{d}s^2 = c^2 \mathrm{d} t^2 - \mathrm{d} \vec{x}^2.$$

The ##-## signs make all the difference!

Usually you depict only one-dimensional motions within a planar Minkowski diagram, but you must interpret it not as the Euclidean plane you are used to from elementary-geometry school geometry. All the measures of lengths are to be inferred from the Minkowski product rather than the usual scalar product of Euclidean (affine) space. The Minkowski plane thus is rather a kind of hyperbolic plane than a Euclidean one, i.e., the temporal and spatial unit lengths are defined by hyperbolas,

$$(ct)^2-x^2=\pm 1,$$

rather than circles as in the Euclidean plane.

Then, very importantly, there are also "null lines", given by light-like curves. In Minkowski space these define the light cone. In the plane it's given by

$$(c t)^2-x^2=0.$$

For details, see my SRT FAQ article,