“The reader may ask why in this book string theory and supersymmetry have not been discussed. … The fact is that this book is about physics and this implies that the theoretical ideas discussed must be supported by experimental facts. Neither supersymmetry and string theory satisfy this criterion. They are figments of the theoretical mind.”

—  Martinus J. G. Veltman

[Martinus Veltman, Facts and mysteries in elementary particle physics, World Scientific, 2003, 981238149X, 308, https://books.google.com/books?id=CNCHDIobj0IC&pg=PA308]

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Martinus J. G. Veltman3
Dutch physicist 1931

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