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 ______      ___     _    _     ______    _____   
|      \\   / _ \\  | || | ||  /_   _//  /  ___|| 
|  --  //  | / \ || | || | ||   -| ||-  | // __   
|  --  \\  | \_/ || | \\_/ ||   _| ||_  | \\_\ || 
|______//   \___//   \____//   /_____//  \____//  
`------`    `---`     `---`    `-----`    `---`

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Text this: On the dual pairs (O(p, q), SL(2, ℝ)), (U(p,q), U(1, 1)) and (Sp(p, q), O*(4))