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We study the energy-momentum tensor and the equation of state as well as the chiral condensate in (2+1)-flavor QCD at the physical point applying the method of Makino and Suzuki based on the gradient flow. We adopt a nonperturbatively O(a)-improved Wilson quark action and the renormalization group-improved Iwasaki gauge action. At Lattice 2016, we have presented our preliminary results of our study in (2+1)-flavor QCD at a heavy u, d quark mass point. We now extend the study to the physical point and perform finite-temperature simulations in the range T \simeq 155--544 MeV (Nt = 4--14 including odd Nt's) at a \simeq 0.09 fm. We show our final results of the heavy QCD study and present some preliminary results obtained at the physical point so far., Comment: 8 pages, 15 figures, talk presented at the 35th International Symposium on Lattice Field Theory (LATTICE 2017), 18-24 June 2017, Granada, Spain

The energy-momentum tensor plays an important role in QCD thermodynamics. Its expectation value contains information of the pressure and the energy density as its diagonal part. Further properties like viscosity and specific heat can be extracted from its correlation function. Recently a new method based on the gradient flow was introduced to calculate the energy-momentum tensor on the lattice, and has been successfully applied to quenched QCD. In this paper, we apply the gradient flow method to calculate the energy-momentum tensor in (2+1)-flavor QCD. As the first application of the method with dynamical quarks, we study at a single but fine lattice spacing a=0.07 fm with heavy u and d quarks ($m_��/m_��=0.63$) and approximately physical s quark. Performing simulations on lattices with Nt=16 to 4, the temperature range of T=174-697 MeV is covered. We find that the results of the pressure and the energy density by the gradient flow method are consistent with the previous results using the T-integration method at T350 MeV (Nt, 49 pages, 20 figures, published version, a typo in Eq. (C7) is corrected; all the simulation results are not changed

We study a reweighting method aiming at numerical studies of QCD at finite density, in which the conventional Monte-Carlo method cannot be applied directly. One of the most important problems in the reweighting method is the overlap problem. To solve it, we propose to perform simulations at several simulation points and combine their results in the data analyses. In this report, we introduce this multipoint reweighting method and test if the method works well by measuring histograms of physical quantities. Using this method, we calculate the meson masses as continuous functions of the gauge coupling beta and the hopping parameters kappa in QCD at zero density. We then determine lines of constant physics in the (beta, kappa) space and evaluate the derivatives of the lattice spacing with respect to beta and kappa along the lines of constant physics (inverse of the beta functions), which are needed in a calculation of the equation of state., 7 pages, 9 figures, talk presented at the 32nd International Symposium on Lattice Field Theory - Lattice 2014, June 23-28, 2014, Columbia University New York, NY