20 research outputs found
Dirac-mode expansion for confinement and chiral symmetry breaking
We develop a manifestly gauge-covariant expansion and projection using the
eigen-mode of the QCD Dirac operator. Applying this method to the Wilson loop
and the Polyakov loop, we perform a direct analysis of the correlation between
confinement and chiral symmetry breaking in SU(3) lattice QCD calculation on
6^4 at beta=5.6 at the quenched level. Notably, the Wilson loop is found to
obey the area law, and the slope parameter corresponding to the string tension
or the confinement force is almost unchanged, even after removing the low-lying
Dirac modes, which are responsible to chiral symmetry breaking. We find also
that the Polyakov loop remains to be almost zero even without the low-lying
Dirac modes, which indicates the Z_3-unbroken confinement phase. These results
indicate that one-to-one correspondence does not hold between confinement and
chiral symmetry breaking in QCD.Comment: 7 pages, 6 figures, Talk given at Conference: Lattice 201
Mirage in Temporal Correlation functions for Baryon-Baryon Interactions in Lattice QCD
Single state saturation of the temporal correlation function is a key
condition to extract physical observables such as energies and matrix elements
of hadrons from lattice QCD simulations. A method commonly employed to check
the saturation is to seek for a plateau of the observables for large Euclidean
time. Identifying the plateau in the cases having nearby states, however, is
non-trivial and one may even be misled by a fake plateau. Such a situation
takes place typically for the system with two or more baryons. In this study,
we demonstrate explicitly the danger from a possible fake plateau in the
temporal correlation functions mainly for two baryons ( and ), and
three and four baryons ( and as well, employing
(2+1)-flavor lattice QCD at GeV on four lattice volumes with
2.9, 3.6, 4.3 and 5.8 fm. Caution is given for drawing conclusion on the
bound , and systems only based on the temporal correlation
functions.Comment: 32 pages, 13 figures, minor corrections, published version, typos
correcte
A travel guide to the canonical bundle formula
We survey known results on the canonical bundle formula and its applications
in algebraic geometry.Comment: 17 pages, to appear in the Proceedings of the conference Birational
Geometry and Moduli Space
QCD and strongly coupled gauge theories : challenges and perspectives
We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe