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Gerardus't Hooft was the PhD student of Martinus Veltman. Veltman, a Dutch theoretical physicist, is known for his work on the Standard Model of particle physics.'t Hooft, also a Dutch theoretical physicist, is known for his contributions to gauge theory and particle physics. He shared the 1999 Nobel Prize in Physics with Veltman for their work on the renormalization of non-Abelian gauge theories.