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"When Google first announced the project they didn't discuss how the nanoparticles would relay their findings. But, in a video from The Atlantic, employees explain that they'll be using light signals to talk to the wristband through the superficial veins on the underside of the wrist. Of course, shining lights through the skin means factoring in a range of skin types and colors, and so Google's scientists have built fake arms with "the same autofluoresecence and biochemical components of real arms." Thus the fake skin."

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AuthorKatina Michael