Changes

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Spatial translations:

Spatial translations:

<br> <math>T_x : (x, &nbsp; y, z, ct) = (x + \epsilon , y, z, ct)</math>

<br> <math>T_x : (x, y, z, ct) = (x + \epsilon , y, z, ct)</math>

<br> <math>T_y : (x, y, z, ct) = (x, y + \epsilon , z, ct)</math>

<br> <math>T_y : (x, y, z, ct) = (x, y + \epsilon , z, ct)</math>

<br> <math>T_z : (x, y, z, ct) = (x, y, z + \epsilon , ct)</math>

<br> <math>T_z : (x, y, z, ct) = (x, y, z + \epsilon , ct)</math>