27,863 research outputs found
Lattice QCD thermodynamics with Wilson quarks
We review studies of QCD thermodynamics by lattice QCD simulations with
dynamical Wilson quarks. After explaining the basic properties of QCD with
Wilson quarks at finite temperature including the phase structure and the
scaling properties around the chiral phase transition, we discuss the critical
temperature, the equation of state and heavy-quark free energies.Comment: Talk at Yukawa International Seminar 2006 (Kyoto), 8 pages, 8 figure
Phase structure of hot dense QCD by a histogram method
We study the phase structure of QCD at high temperature and density by
lattice QCD simulations adopting a histogram method. The quark mass dependence
and the chemical potential dependence of the nature of phase transition are
investigated focusing on the probability distribution function (histogram). The
shape of the distribution function changes with the quark mass and chemical
potential. Through the shape of the distribution, the critical surface which
separates the first order transition and crossover regions in the heavy quark
region is determined for the (2+1)-flavor case. Moreover, we determined the
critical point at finite density for two-flavor QCD with an intermediate quark
mass, using a Gaussian approximation of the complex phase distribution of the
quark determinant. The chemical potential dependence of the critical quark mass
is also evaluated in the situation where two light quarks and many massive
quarks exist. We find that the first order transition region becomes wider with
the chemical potential in the many-flavor QCD.Comment: 16 pages, 20 figures, mini-revie
Non-locality as an essential feature of brane worlds
Weak gravity in the brane world scenario with a scalar field in the bulk
between two end-of-the-world branes is investigated by using the doubly gauge
invariant formalism. We review the result that Einstein gravity is restored in
the low energy limit and that high-energy corrections to Einstein gravity can
be mimicked by higher derivative terms. After that, it is argued that
non-locality is one of essential features of brane worlds.Comment: 8 pages, 3 figures, 1 table, to be published in the proceedings of
the YITP workshop "Braneworld -- Dynamics of spacetime with boundary --
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