The dual Meissner effect in SU(2) Landau gauge

The dual Meissner effect is observed without monopoles in quenched SU(2) QCD with Landau gauge-fixing. Abelian as well as non-Abelian electric fields are squeezed. Magnetic displacement currents which are time-dependent Abelian magnetic fields play a role of solenoidal currents squeezing Abelian electric fields. Monopoles are not always necessary to the dual Meissner effect. The squeezing of the electric flux means the dual London equation and the massiveness of the Abelian electric fields as an asymptotic field. The mass generation of the Abelian electric fields is related to a gluon condensate $\neq 0$ of mass dimension 2.Comment: 10 page, 12 Postscript figures, Talk presented at Quark Confinement and the Hadron Spectrum VI 2004, Sardinia, 21-25 Sep 200

Gauge invariance of color confinement due to the dual Meissner effect caused by Abelian monopoles

The mechanism of non-Abelian color confinement is studied in SU(2) lattice gauge theory in terms of the Abelian fields and monopoles extracted from non-Abelian link variables without adopting gauge fixing. Firstly, the static quark-antiquark potential and force are computed with the Abelian and monopole Polyakov loop correlators, and the resulting string tensions are found to be identical to the non-Abelian string tension. These potentials also show the scaling behavior with respect to the change of lattice spacing. Secondly, the profile of the color-electric field between a quark and an antiquark is investigated with the Abelian and monopole Wilson loops. The color-electric field is squeezed into a flux tube due to monopole supercurrent with the same Abelian color direction. The parameters corresponding to the penetration and coherence lengths show the scaling behavior, and the ratio of these lengths, i.e, the Ginzburg-Landau parameter, indicates that the vacuum type is near the border of the type1 and type2 (dual) superconductor. These results are summarized that the Abelian fundamental charge defined in an arbitrary color direction is confined inside a hadronic state by the dual Meissner effect. As the color-neutral state in any Abelian color direction corresponds to the physical color-singlet state, this effect explains non-Abelian color confinement and supports the existence of a gauge-invariant mechanism of color confinement due to the dual Meissner effect caused by Abelian monopoles.Comment: 11 pages, 14 figure

The Dual Meissner Effect and Magnetic Displacement Currents

The dual Meissner effect is observed without monopoles in quenched $SU (2)$ QCD with Landau gauge-fixing. Magnetic displacement currents which are time-dependent Abelian magnetic fields play a role of solenoidal currents squeezing Abelian electric fields. Monopoles are not always necessary to the dual Meissner effect. The squeezing of the electric flux means the dual London equation and the massiveness of the Abelian electric fields as an asymptotic field. The mass generation of the Abelian electric fields is related to a gluon condensate $\neq 0$ of mass dimension 2.Comment: 4 pages, 5 Postscript figures, title modified, some references added, minor changes made ; Accepted for publication in Phys.Rev.Let

Abelian dominance and the dual Meissner effect in local unitary gauges in SU(2) gluodynamics

Performing highly precise Monte-Carlo simulations of SU(2) gluodynamics, we observe for the first time Abelian dominance in the confining part of the static potential in local unitary gauges such as the F12 gauge. We also study the flux-tube profile between the quark and antiquark in these local unitary gauges and find a clear signal of the dual Meissner effect. The Abelian electric field is found to be squeezed into a flux tube by the monopole supercurrent. This feature is the same as that observed in the non-local maximally Abelian gauge. These results suggest that the Abelian confinement scenario is gauge independent. Observing the important role of space-like monopoles in the Polyakov gauge also indicates that the monopoles defined on the lattice do not necessarily correspond to those proposed by 't Hooft in the context of Abelian projection.Comment: 4 pages, 7 figure

Distal gastrectomy via minilaparotomy for non-overweight patients with T1N0-1 gastric cancer: Initial experience of 30 cases

AbstractMinilaparotomy is considered to be a useful treatment alternative to laparoscopic-assisted surgery from the viewpoint of minimal invasiveness, although it has several limitations for the resection of malignant tumors. We evaluated the usefulness of distal gastrectomy via minilaparotomy for non-overweight patients with clinically diagnosed T1N0-1 gastric cancer. Clinicopathological and surgical data on 30 patients attempted to undergo distal gastrectomy via minilaparotomy (skin incision, ≤7cm) without laparoscopic assistance were analyzed. Inclusion criteria were clinically (preoperatively) diagnosed T1N0-1 gastric cancer that was not suitable for endoscopic mucosal resection located in the middle- or lower-third of the stomach and the patient body mass index ≤ 25.0 kg/m2. The minilaparotomy approach was successful in 27 patients (90%), while laparoscopic assistance was required to accomplish the procedures in three patients (10%). The type of lymph node dissection was D1 + α in 23 patients and D1 + β in 7 patients. The duration of surgery was 105–170 min (median, 143.5 min) and blood loss was 25–520 mL (median, 152.5 mL). Pathological stage was stage IA in 26 patients, IB in two patients, and stage II in two patients. Postoperative complications were wound infection in one patient, bleeding in one patient, and anastomotic ulcer in one patient. The length of postoperative stay was 7–41 (median, 11) days. With a median follow-up of 31 months, there was no recurrence. Distal gastrectomy via minilaparotomy seems feasible and safe in the majority of non-overweight patients with clinically diagnosed T1N0 gastric cancer