Large Scale Simulations of Lattice Gauge Theory: Key NSF Project of China and Recent Developments Zhongshan (Sun Yat-Sen) University, Guangzhou, ChinaXiang-Qian Luo Chinese physicists have been involved in the study of lattice gauge theory since early 80's. Institute of High Energy Physics, Beijing Institute of Theoretical Physics, Beijing Peking Uniniversity, Beijing Nankai University, Tianjin Sichuan University, Chengdu Zhejiang University, Huangzhou Zhongshan University, Guangzhou Beijing Tianjin Chengdu Huangzhou Guangzhou Most investigations in 80 s were analytical, due to limited computational facilities. For review, S.H. Guo and X.Q.Luo, hep-lat/ Thanks to (1) rapid development of high performance supercomputers in China in late 90's, (2) success of the Symanzik improvement program, (3) support from NSF (National Science Foundation), more and more Chinese physicists do numerical simulations. Top 500 Supercomputers in the world, 2002 DeepComp 1800 Legend Group DeepComp P4 Xeon 2 GHz - Myrinet/ 512CPU (NODES) Rmax:1.046 Tflops Rpeak: Tflops Location: Beijing, China Number 43 of top 500 supercomputers 2002 The 3 rd fastest in Asia? Zhongshan U. self-made PC cluster, 2000 NSFC: National Science Foundation Committee: established in 1986 an organization directly affiliated to the State Council for the management of the National Natural Science Fund. General project: ~100K yuan for 3 years. (1 Yuan=1/8USD) NSF project for distinguished young scientists: ~ 0.8M yuan for 4 years. Key NSF project: ~1M yuan for 4 years Approved NSF Funds in China These years, the Chinese lattice physicists received a lot of supports from NSFC and other sources: T.L. Chen, Nankai U., General project, ~100K yuan S.H. Guo, Zhongshan U., Guangzhou, General project, ~100K yuan C. Liu, Peking U., Beijing, General project, ~100K yuan J.M. Liu, Zhongshan U., General project, ~100K yuan X.Q. Luo, Zhongshan U., General project, ~100K yuan J.M. Wu, IHEP, Beijing, General project, ~100K yuan H.P. Ying, Zhejiang U., Huangzhou, General project, ~100K yuan X.Q. Luo, Zhongshan U., NSF project for distinguished young scientists: 0.8M yuan ( ) X.Q. Luo, Q.Z. Chen, Y. Chen, Y.Z. Fang, S.H. Guo, C.Q. Huang, C. Liu, Z.H. Mei, H.P. Ying, Key NSF project: 1.2M yuan ( ) Improved Lattice QCD The most efficient way to reduce the O(a) and finite volume errors Improved scalar action (Symanzik, 1983) Quark action: Hamber and Wu, Phys. Lett. B133 (1983) 351. (Sheikholeslami and Wohlert, 1985 ) Improved gluon action (Luscher, Weisz, 1984) Tadpole improvement (Lepage, 1996) Improved quark Hamiltonian: Luo, Chen, Xu, Jiang,, Phys. Rev. D50 (1994) 501. Jiang, Luo, Mei, Jirari, Kroger, Wu, Phys. Rev. D59 (1999) Improved gluon Hamiltonian: Luo, Guo, Kroger, Schutte, Phys. Rev. D59 (1999) Algorithms To do numerical simulations with clover fermions: Luo, Comput. Phys. Commun. 94 (1996) Jansen and Liu, Comput. Phys. Commun. 99 (1997) 221. To do numerical simulations with Ginsparg-Wilson fermions: Liu, Nucl. Phys. B554 (1999) 313. To do numerical simulations with Kogut-Susskind fermions in the chiral limit: Luo, Mod. Phys. Lett. A16 (2001) Which extends the following algorithm to QCD: Azcoiti, Di Carlo, Grillo, Phys. Rev. Lett. 65 (1990) Azcoiti, Laliena, Luo, Piedrafita, Di Carlo, Galante, Grillo Fernandez, Vladikas, Phys. Rev. D48 (1993) 402. Problems of standard Langrangian Monte Carlo simulations: (1)Extremely difficult to study excited states, (2)Broken done in QCD at finite density. Hamiltonian formulation of LGT doest encounter above problem. Monte Carlo Hamiltonian : to construct effective Hamiltonian from standard Monte Carlo simulations. Tested in quantum mechanics: Jirari, Kroger, Luo, Moriarty, Phys. Lett. A258 (1999) 6. Luo, Jiang, Huang, Jirari, Kroger, Moriarty, Physica A281 (2000) 201. Tested in the scalar model: Huang, Kroger, Luo, Moriarty, Phys. Lett. A299 (2002) 483. Glueball Spectrum from Improved gluon action Morningstar, Peardon, 1997, 1999 Mei, Luo, 2002: New data at larger lattice and M G (0 ++ )=1733MeV M G (2 ++ )=2408MeV M G (1 +- ) =2951MeV Glueballs can also mix with mesons, and decay (to be investigated) Hybrid meson spectrum from Improved gluon action and quark action X.Q. Luo, Z.H. Mei, ``Hybrid Mesons from Anisotropic Lattice QCD with the Clover and Improved Gauge Actions", Nuclear Physics B(P. S.)119 (2003) SCI. [hep-lat/ ]. Z.H. Mei, X.Q. Luo, ``Exotic Mesons from Quantum Chromodynamics with Improved Gluon and Quark Actions on the Anisotropic Lattice", to appear in International Journal of Modern Physics A. SCI. [hep-lat/ ]. Neutron StarNeutron Star RHIC (Relativistic Heavy Ion Collider) LHC (Large Hadron Collider) Lattice QCD at High Temperature can well be investigated by the standard Monte Carlo approach At finite density (chemical potential), standard action approach (Hasenfratz, Kasch, 1983) fails: because S is complex, one can not use e -S to generate configurations Alternative (Hamiltonian): QCD at finite chemical potential was solved in the strong coupling regime: Gregory, Guo, Kroger, Luo, Phys. Rev. D62 (2000) Luo, Gregory, Guo, Kroger, hep-ph/ Fang, Luo, hep-lat/ There is a first order chiral phase transition at c Reasonable results for the physical quantities are obtained, Quantum Instantons and Quantum Chaos: Jirari, Kroger, Luo, Moriarty, Rubin, Phys. Rev. Lett. 86 (2001) 187. Key Project of National Science Foundation "Large Scale Simulations of Lattice Gauge Theory, 120M ( ) Xiang-Qian Luo (Director, Zhongshan U., Guangzou)Xiang-Qian Luo (Director, Zhongshan U., Guangzou) Qi-Zhou Chen (Zhongshan U., Guangzhou) Ying Chen (Institute of High Energy Phys., Beijing) Yi-Zhong Fang (Zhongshan U., Guangzou) Shuo-Hong Guo (Zhongshan U., Guangzou) Chun-Qing Huang (Zhongshan U. and Foshan U.) Chuan Liu (Peking U., Beijing) Da-Qing Liu (Institute of Theoretical Phys., Beijing) Zhong-Hao Mei (Zhongshan U., Guangzou) He-Ping Ying (Zhejiang U., Huangzhou)Qi-Zhou Chen (Zhongshan U., Guangzhou) Ying Chen (Institute of High Energy Phys., Beijing) Yi-Zhong Fang (Zhongshan U., Guangzou) Shuo-Hong Guo (Zhongshan U., Guangzou) Chun-Qing Huang (Zhongshan U. and Foshan U.) Chuan Liu (Peking U., Beijing) Da-Qing Liu (Institute of Theoretical Phys., Beijing) Zhong-Hao Mei (Zhongshan U., Guangzou) He-Ping Ying (Zhejiang U., Huangzhou) We plan to do large scale simulations of lattice QCD, using the parallel supercomputing facilities in China. We will develop new numerical methods and study the following hot topics: new hadrons such as glueballs and hybrid mesons, scattering of hadrons, topology of QCD vacuum, transition from the quark confinement phase to quark-gluon plasma phase, quantum instantons and quantum chaos.