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The Strange Theory of Light

The Quantum electrodynamics (QED) view on light. Twenty-one interactive programs enable the reader to make “experiments” and analyse single- and multiple-slit interference, reflection including total one, diffraction, refraction and dispersion, followed by operation of lenses, parabolic mirror (antenna) and holography.


Prompt calculation of circle on-line.

Calculate quickly circumference or area of circle. It does not matter whether you enter radius or area of circle. Our calculator calculates it immediately.