FLAG Review 2021

Abstract We review lattice results related to pion, kaon, D -meson, B -meson, and nucleon physics with the aim of making them easily accessible to the nuclear and particle physics communities. More specifically, we report on the determination of the light-quark masses, the form factor $$f_+(0)$$ f + ( 0 ) arising in the semileptonic $$K \rightarrow \pi $$ K → π transition at zero momentum transfer, as well as the decay constant ratio $$f_K/f_\pi $$ f K / f π and its consequences for the CKM matrix elements $$V_{us}$$ V us and $$V_{ud}$$ V ud . Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of $$SU(2)_L\times SU(2)_R$$ S U (…

• UD
  U.S. Department of Energy

  Awards: DE-SC0009913, DE-SC0011637, DE-AC05-06OR23177, DE-SC0010120
• UO
  University of Bern
• JI
  Joint Institute for Computational Fundamental Science

  Award: JPMXP1020200105
• NN
  National Natural Science Foundation of China

  Awards: 11775002, 12125501, 12070131001
• GV
  Generalitat Valenciana

  Award: CIDEGENT/2019/040
• DF
  Danmarks Frie Forskningsfond

  Award: 8021-00122B
• MD
  Ministerio de Ciencia e Innovación

  Awards: PID2020-113644GB-I00, PGC2018-094857-B-I00
• H2
  Horizon 2020 Framework Programme

  Awards: 813942, 757646
• SA
  Science and Technology Facilities Council

  Awards: ST/P000711/1, ST/T000775/1, ST/P000711/1, ST/P000630/1, ST/T000600/1, ST/P000630/1, ST/T000775/1
• JS
  Japan Society for the Promotion of Science

  Awards: 16K05320, 18H03710, 21H01085