IFUP-TH 57/95 Improved lattice operators: the case of the topological charge density
نویسندگان
چکیده
We analyze the properties of a class of improved lattice topological charge density operators, constructed by a smearing-like procedure. By optimizing the choice of the parameters introduced in their definition, we find operators having (i) a better statistical behavior as estimators of the topological charge density on the lattice, i.e. less noisy; (ii) a multiplicative renormalization much closer to one; (iii) a large suppression of the perturbative tail (and other unphysical mixings) in the corresponding lattice topological susceptibility.
منابع مشابه
Improved lattice operators: Case of the topological charge density.
We analyze the properties of a class of improved lattice topological charge density operators, constructed by a smearing-like procedure. By optimizing the choice of the parameters introduced in their definition, we find operators having (i) a better statistical behavior as estimators of the topological charge density on the lattice, i.e. less noisy; (ii) a multiplicative renormalization much cl...
متن کاملIfup-th 3/95
where e, e label the helicity states and k is the momentum transfer. In a naive wave function picture G1(0) can be interpreted as the fraction of the nucleon spin carried by the quarks. Experimental determinations lead to an unexpectedly small value of G1(0), calling for a theoretical explanation in the context of a nonperturbative study in QCD. G1(0) can be extracted from the nucleon matrix el...
متن کاملar X iv : h ep - l at / 9 50 10 09 v 1 1 2 Ja n 19 95 Topological Density and Instantons on a Lattice ∗
We present an update on the study of topological structure of QCD. Issues addressed include a comparison between the plaquette and the geometric methods of calculating the topological density. We show that the improved gauge action based on √ 3 blocking transformation suppresses the formation of topologically charged dislocations with low action. Using a cooling method we identify the instanton...
متن کاملTopological charge on the lattice : a field theoretical
We construct sequences of "field theoretical" lattice topological charge density operators which formally approach geometrical definitions in 2D CP s l models and 4D SU(N) Yang-Mills theories. The analysis of these sequences of operators suggests a new way of looking at the geometrical method, showing that geometrical charges can be interpreted as limits of sequences of field theoretical (analy...
متن کاملCategories of lattice-valued closure (interior) operators and Alexandroff L-fuzzy topologies
Galois connection in category theory play an important role inestablish the relationships between different spatial structures. Inthis paper, we prove that there exist many interesting Galoisconnections between the category of Alexandroff $L$-fuzzytopological spaces, the category of reflexive $L$-fuzzyapproximation spaces and the category of Alexandroff $L$-fuzzyinterior (closure) spaces. This ...
متن کامل