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 __   _      ___                 ___       _____  
| || | ||   / _ \\      ___     / _ \\    / ___// 
| '--' ||  / //\ \\    /   ||  / //\ \\   \___ \\ 
| .--. || |  ___  ||  | [] || |  ___  ||  /    // 
|_|| |_|| |_||  |_||   \__ || |_||  |_|| /____//  
`-`  `-`  `-`   `-`     -|_|| `-`   `-` `-----`   
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Text this: Negative refraction in hyperbolic metamaterials