can someone explain this to me please?
A scalar is just a number. A wave is a repetitive variation in that number. For example the altitude of each point in Wisconsin forms a scalar wave. Or sound waves, all you can hear is the intensity of the superimposed tones; the intensity is just a number (yeah, maybe a complex number) and it varies repetitively (i.e the cycles of the tones).
What context did you find the phrase in?
in regards to Electronic Voice Phenomenon research by Tesla
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