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