Generalized ghost-free propagators in nonlocal field theories

Gluon and ghost propagators from the viewpoint of general principles of quantized gauge field theories

We discuss the possible form of gluon and ghost propagators in the infrared region of Yang-Mills theory in the covariant gauge from the viewpoint of general principles of quantized gauge field theories.

Infrared behavior and infinite-volume limit of gluon and ghost propagators in Yang-Mills theories

Lattice studies of the infrared behavior of gluon and ghost propagators are a key probe of confinement scenarios in Yang-Mills theories. However, finite-volume effects become an important issue as the infrared limit is approached. By considering general quantities — namely an associated susceptibility in the gluon case and properties of the lowest-lying eigenmode of the Faddeev-Popov matrix in ...

Generalized phase field theories

5 Ghost free dual vector theories in 2 + 1 dimensions

We explore here the issue of duality versus spectrum equivalence in abelian vector theories in 2 + 1 dimensions. Specifically we examine a generalized self-dual (GSD) model where a Maxwell term is added to the self-dual model. A gauge embedding procedure applied to the GSD model leads to a Maxwell-Chern-Simons (MCS) theory with higher derivatives. We show that the latter contains a ghost mode c...

Towards singularity- and ghost-free theories of gravity.

We present the most general covariant ghost-free gravitational action in a Minkowski vacuum. Apart from the much studied f(R) models, this includes a large class of nonlocal actions with improved UV behavior, which nevertheless recover Einstein's general relativity in the IR.