The mathematical study of a nonlinear equation 
, where 
maps from a Hilbert space 
to a Hilbert
space 
and 
which abstracts the construction
of optical holograms.
Holography
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References
Lannes, A. "Abstract Holography." J. Math. Anal. Appl. 74, 530-559, 1980.Referenced on Wolfram|Alpha
HolographyCite this as:
Weisstein, Eric W. "Holography." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Holography.html