The Poincaré Group is 10 mathematical transformations that can be applied to different coordinates of the space-time graph (x, y, z, ct), but does not affect the "spacetime interval". The "spacetime interval" is roughly the 4-D equivalent of 3-D "distance".
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The Poincaré Group consists of 10 mathematical transformations that can be applied to different coordinates of the space-time graph (x, y, z, ct), but do not affect the "spacetime interval". The "spacetime interval" is roughly the 4-D equivalent of 3-D "distance".
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The Poincaré Group is a "symmetry group" because the spacetime interval remains invariant.