Zoltan Fodor (physicist)

Last updated
Zoltan Fodor
Born
Budapest, Hungary
Nationality Hungarian, German
Alma mater Eotvos Lorand University, Budapest, Hungary
Known forNumerical Quantum Field Theory, Lattice QCD
Scientific career
FieldsTheoretical Particle Physics

Zoltan Fodor is a Hungarian-German theoretical particle physicist, best known for his works in lattice QCD by numerically solving the theory of the strong interactions.

Contents

Life

In high school and at university he won several national competitions in mathematics, physics and chemistry. He did his undergraduate studies at the Eotvos Lorand University, where he received his PhD in 1990. He was postdoctoral fellow at DESY, Hamburg (Germany), CERN, Geneva (Switzerland) [1] and KEK, Tsukuba (Japan).

In 1998 he became a professor at the Lorand Eotvos University, Budapest, Hungary. In 2003 he moved to the University of Wuppertal, Germany.

Career

Fodor is widely known for his results in lattice QCD. Many of his findings represent the first fully controlled lattice calculations using ab-initio quantum chromodynamics and quantum electrodynamics.

QCD thermodynamics

In 2000 he proposed a method. [2] to circumvent the sign problem at finite baryonic chemical potentials or densities. The numerical sign problem is one of the major unsolved problems in the physics of many particle systems. In 2006 he determined the nature of the QCD transition in the early universe. [3] Since the transition turned out to be an analytic one no observable cosmic relics are expected from this transition. In a series of papers he also calculated the absolute scale of the QCD transition. [4] The equation of state of the strongly interacting matter plays a crucial role both in cosmology and in heavy ion collisions, which he determined in 2010. [5] By calculating the topological susceptibility in the early universe at high temperatures, he gave a prediction for the axion's mass in 2016. Axions are one of the mostly advocated candidates for dark matter.

QCD at vanishing temperature

Since 2005 he has been the spokesperson of the Budapest-Marseille-Wuppertal Collaboration focusing on QCD phenomena at vanishing temperature. In 2008 they determined the light hadron spectrum, which explains the mass of the visible universe [6] In 2015 the mass difference between the neutron and the proton (and other so-called isospin splittings) were calculated. [7] This 0.14 percent neutron-proton mass difference is responsible—among others—for the existence of atoms, as we know them, or for the ignition of stars. In 2021 they determined the anomalous magnetic dipole moment of the muon. This quantity is widely believed to indicate new physics beyond the Standard Model. However, the Budapest-Marseille-Wuppertal Collaboration obtained a theory-based result [8] agreeing more with the experimental value than with the previous theory-based value that relied on the electron-positron annihilation experiments.

Awards

Notes

  1. ↑ Fodor, Z. (1991). "Differences between quark and gluon jets at LEP". Physics Letters B. 263 (2): 305–310. doi:10.1016/0370-2693(91)90605-P.
  2. ↑ Fodor 2002
  3. ↑ Aoki 2006
  4. ↑ Borsanyi 2010
  5. ↑ Borsanyi 2016
  6. ↑ Durr 2008
  7. ↑ Borsanyi 2015
  8. ↑ Borsanyi 2021
  9. ↑ "New members". American Academy of Arts and Sciences. 2023. Retrieved 2023-04-21.
  10. ↑ "Fellows nominated in 2022". APS Fellows archive. American Physical Society. Retrieved 2022-10-19.

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References

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