Dear Colleague, We are organizing the online workshop "QCD phase diagram and lattice QCD" October 25-29 2021 (JST), ZOOM/REMO at YITP, Kyoto U. https://www2.yukawa.kyoto-u.ac.jp/~qcd2021/ sponsored by Yukawa Institute for Theoretical Physics, Kyoto Univ. * Aim of the workshop The purpose of this one-week workshop is to intensively discuss various aspects of QCD at high temperatures as well as at nonzero chemical potentials to explore the phase structure of QCD. For this purpose, we would invite world experts who would trigger discussions of principal questions about QCD. It is assumed that they would present review talks reflecting their vision of QCD at high temperatures and densities, including quark mass dependence. A number of shorter talks will be foreseen by younger researchers and if necessary a poster session will be organized. All talks will be presented on-line. The workshop covers topics in Chiral phase transition Dependence of the QCD phases on quark mass and chemical potential U(1) axial and possible extension of symmetries at finite temperature Energy momentum tensor and EOS Approaches to sign problem at finite density QCD Theoretical developments * The (confirmed) invited speakers Aoki, S. (YITP, Kyoto Univ.) Borsanyi, S. (Univ. of Wuppertal) Cohen, T. (Univ. of Maryland) Ejiri, S. (Niigata Univ.) Fukuma, M. (Kyoto Univ.) Glozman, L. (Univ. of Graz) Hanada, M. (Univ. of Surrey) Hasenfratz, A. (Univ. of Colorado) Hashimoto, S. (KEK/Sokendai) Kitazawa, M. (Osaka Univ.) Lahiri, A. (Bielefeld Univ.) Lombardo, M.P. (INFN Firenze) McLerran, L. (Univ. of Washington) Philipsen, O. (Goethe Univ. Frankfurt) Pisarski, R. (BNL) Shuryak, E. (Stony Brook Univ.) Takeda, S. (Kanazawa Univ.) Yamada, N. (KEK/Sokendai) * Program We plan to have * Asian-American-friendly slot : 9:00-13:00 JST for Monday and Tuesday and * Asian-European-friendly slot : 16:00-20:00 JST for other days. For each slot, there will be invited talks (40min) and short talks (20min). Since it is difficult to prepare many slots available from different places in the world, the number of short talks is limited and we may ask some of presenters to switch from oral to poster presentation. * Online dinner/lunch/breakfast At the end of the workshop, we plan to have an online dinner/lunch/breakfast from 20:00 to 21:00 JST. The participants are encouraged to turn on camera, and prepare their favorite dishes and drinks. * Important Deadlines The deadline for abstract submission : Sep. 30, 2021 The deadline for registration : Oct. 15, 2021 We are looking forward to seeing you soon. Yasumichi Aoki (RIKEN R-CCS) Hidenori Fukaya (Osaka Univ.) Yoshifumi Nakamura (RIKEN R-CCS) qcd2021@yukawa.kyoto-u.ac.jp