==== Updates ====

  * Further discussion of the [[book:gsr:hwangles|
    antenna problem]] ((ss)7.3) can be found [[book:updates:hwangles|here]].
  * A discussion of three-dimensional spacetime diagrams can be found [[
    book:updates:3d|here]].
  * A discussion of using a geometric approach to teach both special and general relativity can be found [[book:updates:geomajp|here]].