On this slide we show "normal " transverse wave interference, as we presently teach it in our textbooks. 
          We visualize two identical transmitters, each producing a beam in a pattern of about 55 degrees of so. 
          Where these beams overlap -- in the ideal, perfect case, we have constructive and destructive interference, with absolute zero-vector linear regions being formed.  We put in the energy, and out-of-phase interference creates the zero zones, which contain no energy as such. 
          We point out, however, that these zero-lines are scalars,
and contain high stresses on spacetime. 

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