Mutual coherence (physics)

Two sinusoidal oscillations of the same frequency are said to be mutually coherent if they exhibit a constant phase relationship during the course of time.

Wolkowski, Z. W. (2007). "The concept of coherence considered as a systems isomorphism". Systems Research. 9 (4): 61–66. doi:10.1002/sres.3850090406. 

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