Topological structure in the SU (2) vacuum

DeGrand, Thomas; Hasenfratz, Anna; Kovács, Tamás

doi:10.1016/s0550-3213(97)00480-x

Cited by 100 publications

(139 citation statements)

References 45 publications

Supporting

Mentioning

130

Contrasting

Order By: Relevance

“…In the recent years instantons have been intensively studied by direct numerical simulations of gluon fields on the lattice, using various configuration-smoothing methods [21,36,37]. A typical snapshot of gluon fluctuations in the vacuum is shown in Fig.…”

Section: Instanton Ensemblementioning

confidence: 99%

See 1 more Smart Citation

Instantons at work

Diakonov

2003

Progress in Particle and Nuclear Physics

350

506

View full text Add to dashboard Cite

The aim of this review is to demonstrate that there exists a coherent picture of strong interactions, based on instantons. Starting from the first principles of Quantum Chromodynamics -via the microscopic mechanism of spontaneous chiral symmetry breakingone arrives to a quantitative description of the properties of light hadrons, with no fitting parameters. The discussion of the importance of instanton-induced interactions in soft high-energy scattering is new.

show abstract

Section: Instanton Ensemblementioning

confidence: 99%

“…If the vacuum is isotropic, one has θ 44 = θ µµ /4. Using the trace anomaly, 36) where β(α s ) is the Gell-Mann-Low function, 37) with b 1,2 given by eq. (1.2), one gets [7]:…”

mentioning

confidence: 99%

Instantons at work

Diakonov

2003

Progress in Particle and Nuclear Physics

350

506

View full text Add to dashboard Cite

show abstract

“…Traditionally, the presence of locally classical excitations like instantons in Monte Carlo lattice gauge fields has been explored by using methods like cooling [26,27,28,29], restricted cooling [30], smearing [31], that replaced the more demanding RG cycling [32,33], and more general, by combinations of blocking and inverse blocking [34,35,36]. In the result, a well-localized topological charge density (according to its field-theoretical definition [37,38]) becomes visible.…”

Section: Introductionmentioning

confidence: 99%

Calorons and dyons at the thermal phase transition analyzed by overlap fermions

et al. 2007

View full text Add to dashboard Cite

In a pilot study, we use the topological charge density defined by the eigenmodes of the overlap Dirac operator (with ultraviolet filtering by mode-truncation) to search for lumps of topological charge in SU (2) pure gauge theory. Augmenting this search with periodic and antiperiodic temporal boundary conditions for the overlap fermions, we demonstrate that the lumps can be classified either as calorons or as separate caloron constituents (dyons). Inside the topological charge clusters the (smeared) Polyakov loop is found to show the typical profile characteristic for calorons and dyons. This investigation, motivated by recent caloron/dyon model studies, is performed at the deconfinement phase transition for SU (2) gluodynamics on 20 3 × 6 lattices described by the tadpole improved Lüscher-Weisz action. The transition point has been carefully located. As a necessary condition for the caloron/dyon detection capability, we check that the LW action, in contrast to the Wilson action, generates lattice ensembles, for which the overlap Dirac eigenvalue spectrum smoothly behaves under smearing and under the change of the boundary conditions.

show abstract

“…The nonperturbative QCD vacuum is a very complicated medium and its dynamical and topological complexity [1][2][3] means that its structure can be organized at various levels (classical, quantum). It can contain many different components and ingredients which contribute to the truly nonperturbative vacuum energy density (VED), one of the main characteristics of the QCD ground state.…”

Section: Introductionmentioning

confidence: 99%

Determination of the quantum part of the truly nonperturbative Yang-Mills vacuum energy density in covariant gauge QCD

Gogohia¹,

Kluge²

2000

Phys. Rev. D

View full text Add to dashboard Cite

Using the effective potential approach for composite operators, we have formulated a general method of calculation of the truly nonperturbative YangMills vacuum energy density in the covariant gauge QCD ground state quantum models. It is defined as an integration of the truly nonperturbative part of the full gluon propagator over the deep infrared region (soft momentum region). A nontrivial minimization procedure makes it possible to determine the value of the soft cutoff in terms of the corresponding nonperturbative scale parameter, which is inevitably present in any nonperturbative model for the full gluon propagator. We have shown for specific models of the full gluon propagator explicitly that the use of the infrared enhanced and finite gluon propagators lead to the vacuum energy density which is finite, always negative and it has no imaginary part (stable vacuum), while the infrared vanishing propagators lead to unstable vacuum and therefore they are physically unacceptable.

show abstract

Topological structure in the SU (2) vacuum

Cited by 100 publications

References 45 publications

Instantons at work

Instantons at work

Calorons and dyons at the thermal phase transition analyzed by overlap fermions

Determination of the quantum part of the truly nonperturbative Yang-Mills vacuum energy density in covariant gauge QCD

Contact Info

Product

Resources

About