Chiral Fermions on the Lattice

A recently proposed method for regularizing chiral gauge theories non-perturbatively is discussed in detail. The result is an effective action which can be computed from the lattice gauge field, and which is suited for numerical simulations.Comment: Talk given by G. Schierholz at Yukawa International Seminar on Non-Perturbative QCD: Structure of the QCD Vacuum (YKIS97), Kyoto, December 1997; typos correcte

Instantons or monopoles? Dyons

Non-Abelian gauge theories can be cast into Abelian gauge theories with monopoles. We ask what becomes of the instantons after abelian projection. Instantons are found to consist of closed dyon loops. It is shown that the electric charge of the dyons is quantized. The implication of this result for the dynamics of the Yang-Mills vacuum is briefly discussed. (orig.)27 refs.SIGLEAvailable from TIB Hannover: RA 2999(96-069) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

On the eta-invariant in the 4D chiral U(1) theory

SIGLEAvailable from TIB Hannover: RA 2999(00-003) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

On the eta-invariant in the four dimensional chiral U(1) theory

The imaginary part of the effective action is investigated in the 4D chiral U(1) theory using the CFA. (orig.)SIGLEAvailable from TIB Hannover: RA 2999(99-140) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Lattice chiral fermions in the background of non-trivial topology

We address the problem of numerical simulations in the background non-trivial topology in the chiral Schwinger model. An effective fermionic action is derived which is in accord with established analytical results, and which satisfies the anomaly equation. We describe a numerical evaluation of baryon number violating amplitudes, specifically the 't Hooft vertex. (orig.)15 refs.SIGLEAvailable from TIB Hannover: RA 2999(99-130) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Lattice chiral Schwinger model: selected results

We discuss a method for regularizing chiral gauge theories. The idea is to formulate the gauge fields on the lattice, while the fermion determinant is regularized and computed in the continuum. A simple effective action emerges which lends itself to numerical simulations. (orig.)SIGLEAvailable from TIB Hannover: RA 2999(98-043) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Is the chiral U(1) theory trivial?

The chiral U(1) theory differs from the corresponding vector theory by an imaginary contribution to the effective action which amounts to a phase factor in the partition function. The vector theory, i.e. QED, is known to be trivial in the continuum limit. It is argued that the presence of the phase factor will not alter this result and the chiral theory is non-interacting as well. (orig.)SIGLEAvailable from TIB Hannover: RR 2999(00-161) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Structure of the baryonic flux tube in N_f=2 lattice QCD at finite temperature

We study the flux tube profile in the baryonic system in full QCD at finite temperature of N_t=8 lattice. We fix the maximally Abelian gauge and measure the monopole and the photon parts of the Abelian action density, the color electric field and the monopole current on both sides of the finite temperature transition. We demonstrate the disappearance of the flux tube in the high temperature phase. (orig.)Available from TIB Hannover: RA 2999(03-144) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman