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Gerard 't Hooft
1993· Person
ProvenTested many times; part of working physics.
Gerard 't Hooft (born 1946) is a Dutch theoretical physicist at Utrecht University and a 1999 Nobel laureate.
See it on the Science map →How it works
As a 24-year-old graduate student under Martinus Veltman, 't Hooft proved in 1971 that the theories behind the Standard Model give sensible, finite answers, which won them the 1999 Nobel Prize. He works by stubborn, careful counting. In 1993, counting how much information a black hole can hold, he proposed that everything inside a region of space could be fully described by data on its boundary surface: the first statement of the holographic principle.
Why it matters
He made the Standard Model a working calculating machine, and he started the holographic idea that now drives much research on quantum gravity and black holes.
How the work held up
His 1971-72 work was confirmed by precision tests: the W and Z particles found at CERN in 1983 and the Higgs in 2012. His holographic idea gained support from Maldacena's AdS/CFT in 1997.
Still a mystery
He argues quantum randomness hides a deterministic, clockwork layer underneath (his "cellular automaton" view). Most physicists are unconvinced, and it remains untested.
Connections (2)
▸Gerard 't Hooft proposed The holographic principleSpeculative
The relationship
't Hooft counted the number of independent quantum states a region of space could hold. Because packing in too much creates a black hole whose entropy scales with area, he concluded the true count tracks surface area. He proposed that physics inside could be described by roughly one bit per tiny Planck-sized patch of the boundary.
How the link was found
Gerard 't Hooft, in his 1993 paper "Dimensional reduction in quantum gravity," which compared the idea to a hologram.
Is it proven?
It follows logically from black-hole entropy. AdS/CFT (1997) later realized it precisely in model universes. It is untested in our universe.
Open questions and mysteries
't Hooft hoped it would point to a deterministic theory underneath; most others took it in different directions. Which reading is right is unknown.
▸Gerard 't Hooft proved the math consistent (Nobel 1999) The Standard ModelProven
The relationship
Early versions of the Standard Model gave infinite, meaningless answers in detailed calculations. 't Hooft proved the infinities could be systematically removed, a property called renormalizability. That turned the electroweak theory from a promising sketch into a precise calculator.
How the link was found
Gerard 't Hooft with his adviser Martinus Veltman at Utrecht, 1971-72. They shared the 1999 Nobel Prize in Physics.
Why it's proven
The theory's precise predictions were confirmed: W and Z particles at CERN in 1983, the top quark's mass before its 1995 discovery, and the Higgs boson in 2012.
Open questions and mysteries
Why the Standard Model's parameters have their values, and how to include gravity, remain open.