Dina Rubina. The Handwriting Of Leonardo (№ 355555)

... invented the ball, called it "Orb-invisible." Top of the facet structure, plastic coated... And inside... you wouldn't believe. Hanging in olszany a giant ball. Remote control opens - pulls to the side, with a rectangular segment in the side, but within absolute, pitch-black this velvet darkness. And if you stick your hand inside - the hand disappears. The effect of cosmic "black hole". She explained, I understood nothing. Well, not good, never was good at science. Knew only that the idea in itself for itself, a closed system of mirrors.
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- This is not fiction, uncles Lesh. This is physics. Here the same effect that cosmic black hole's gravitational pull is so great that it can not leave even objects moving at the speed of light. Hence, the light can not from this hole to escape!