Related papers: Partial twisting for scalar mesons
The partial scaling transform of the density matrix for multiqubit states is introduced to detect entanglement of quantum states. The transform contains partial transposition as a special case. The scaling transform corresponds to partial…
In the first part of the talk, I review what we know (or rather do not know) about the structure of the QCD vacuum in the presence of strange quarks. Chiral perturbation theory allows to study reactions of pions and kaons and to further…
It is sometimes speculated that the sign problem that afflicts many quantum field theories might be reduced or even eliminated by choosing an alternative domain of integration within a complexified extension of the path integral (in the…
We confront the finite volume and small quark mass behaviour of the scalar condensate, determined numerically in quenched lattice QCD using Neuberger fermions, with predictions of quenched chiral perturbation theory. We find that quenched…
This talk presents some results relevant for lattice QCD at higher order in ChPT. First we discuss the finite volume corrections at two loops for the quark condensate as well as a L\"uscherlike finite volume formula for it. The latter…
We discuss recent progress made studies of bulk thermodynamics of strongly interacting matter through lattice simulations of QCD with an almost physical light and strange quark mass spectrum. We present results on the QCD equation of state…
We discuss the role of the U(1) axial symmetry for the phase structure of QCD at finite temperature. In particular, supported by recent lattice results, we analyse a scenario in which a U(1)-breaking condensate survives across the chiral…
Using a chiral random matrix theory we can now derive the low energy partition functions and Dirac eigenvalue correlations of QCD with different chemical potentials for the dynamical and valence quarks. The results can also be extended to…
I report on first results of the ETMC obtained simulating lattice QCD with two degenerate flavours of Wilson twisted mass fermions, for which physical observables are automatically O(a) improved. Recent improvements of the HMC algorithm…
The study of nuclear physics using lattice QCD is hindered by an exponentially large signal-to-noise problem which is conventionally alleviated by raising the quark masses to unphysically high values. We propose a novel form of partial…
I report the results of a series of works on the phase diagram of theories with a different number of colors and/or quarks in a different representation than in QCD. Similarities as well as differences as compared to the real world are…
We review recent work by the ALPHA and UKQCD Collaborations where masses and matrix elements were computed in lattice QCD using Schr\"odinger functional boundary conditions and where the strange quark mass was determined in the quenched…
It is shown how on-shell O(a) improvement can be implemented non-perturbatively in lattice QCD with Wilson quarks. Improvement conditions are obtained by requiring the PCAC relation to hold exactly in certain matrix elements. These are…
We review the current state of knowledge of the phase diagram of QCD through lattice, effective field theories, and chiral models. Several sections through the three dimensional phase diagram are known for $N_f=2+1$ with good precision. Due…
In the past year domain wall fermion simulations have moved from exploratory stages to the point where systematic effects can be studied with different gauge couplings, volumes, and lengths in the fifth dimension. Results are presented here…
The topology conserving gauge action proposed by Luescher is expected to reduce the number of non-smooth gauge configurations as well as the topology change compared to the conventional actions for the same lattice spacings. We report our…
It was recently observed in a lattice QCD measurement that the chiral condensate in the quenched approximation shows dramatically different behavior in the three $Z_3$-equivalent de-confined phases. We argue that this phenomenon can be…
We outline a connection between scalar quark confinement, a phenomenologically successful concept heretofore lacking fundamental justification, and QCD. Although scalar confinement does not follow from QCD, there is an interesting and close…
Wilson's formulation of lattice QCD is attractive for many reasons, but perhaps mainly because of its simplicity and conceptual clarity. Numerical simulations of the Wilson theory (and of its improved versions) tend to be extremely…
We develop chiral perturbation theory for baryons in quenched QCD. Quenching (the elimination of diagrams containing virtual quark loops) is achieved by extending the Lagrangian method of Bernard and Golterman, and is implemented in a…