1,429 research outputs found
Parameter from Dynamical Rearrangement of U(1) and Parameter
We study the generation of parameter from the dynamical rearrangement
of local U(1) symmetry in a five-dimensional model and discuss phenomenological
implications on the parameter, under the assumption that supersymmetry
is broken by the Scherk-Schwarz mechanism.Comment: 16 page
Family number, Wilson line phases and hidden supersymmetry
We study the relationship between the family number of chiral fermions and
the Wilson line phases, based on the orbifold family unification. We find that
flavor numbers are independent of the Wilson line phases relating
extra-dimensional components of gauge bosons, as far as the standard model
gauge symmetry is respected. This feature originates from a hidden
quantum-mechanical supersymmetry.Comment: 17 pages, 1 figur
Quarkyonic matter in lattice QCD at strong coupling
We study the phase diagram of quark matter at finite temperature and density
in the strong coupling lattice QCD with one species of unrooted staggered
fermions including finite coupling () effects for color SU(). We
find that we may have partially chiral restored medium density matter at
, which would correspond to the quarkyonic matter suggested at large
.Comment: 9 pages, 4 figure
Chiral and deconfinement transitions in strong coupling lattice QCD with finite coupling and Polyakov loop effects
We investigate chiral and deconfinement transitions in the framework of the
strong coupling lattice QCD for color SU(3) with one species of unrooted
staggered fermion at finite temperature and quark chemical potential. We take
account of the leading order Polyakov loop terms as well as the
next-to-next-to-leading order (1/g^4) fermionic terms of the strong coupling
expansion in the effective action. We investigate the Polyakov loop effects by
comparing two approximation schemes, a Haar measure method (no fluctuation from
the mean field) and a Weiss mean-field method (with fluctuations). The
effective potential is obtained in both cases, and we analytically clarify the
Polyakov loop contributions to the effective potential. The Polyakov loop is
found to suppress the chiral condensate and to reduce the chiral transition
temperature at mu=0, and the chiral transition temperature roughly reproduces
the Monte Carlo results at beta=2N_c/g^2 \lesssim 4. The deconfinement
transition is found to be the crossover and first order for light (am_0
\lesssim 4 at beta=4) and heavy quark masses, respectively.Comment: 13 pages, 15 figures. v2; More dicussions added, figures improved,
and typos correcte
Another mean field treatment in the strong coupling limit of lattice QCD
We discuss the QCD phase diagram in the strong coupling limit of lattice QCD
by using a new type of mean field coming from the next-to-leading order of the
large dimensional expansion. The QCD phase diagram in the strong coupling limit
recently obtained by using the monomer-dimer-polymer (MDP) algorithm has some
differences in the phase boundary shape from that in the mean field results. As
one of the origin to explain the difference, we consider another type of
auxiliary field, which corresponds to the point-splitting mesonic composite.
Fermion determinant with this mean field under the anti-periodic boundary
condition gives rise to a term which interpolates the effective potentials in
the previously proposed zero and finite temperature mean field treatments.
While the shift of the transition temperature at zero chemical potential is in
the desirable direction and the phase boundary shape is improved, we find that
the effects are too large to be compatible with the MDP simulation results.Comment: Talk given at 28th International Symposium on Lattice Field Theory
(Lattice 2010), Villasimius, Sardinia, Italy, 14-19 June, 201
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