Algebraic Properties of BRST Coupled Doublets

We characterize the dependence on doublets of the cohomology of an arbitrary nilpotent differential s (including BRST differentials and classical linearized Slavnov-Taylor (ST) operators) in terms of the cohomology of the doublets-independent component of s. All cohomologies are computed in the space of local integrated formal power series. We drop the usual assumption that the counting operator for the doublets commutes with s (decoupled doublets) and discuss the general case where the counting operator does not commute with s (coupled doublets). The results are purely algebraic and do not rely on power-counting arguments.Comment: Some explanations enlarged, references adde

Comments on the Equivalence between Chern-Simons Theory and Topological Massive Yang-Mills Theory in 3D

The classical formal equivalence upon a redefinition of the gauge connection between Chern-Simons theory and topological massive Yang-Mills theory in three-dimensional Euclidean space-time is analyzed at the quantum level within the BRST formulation of the Equivalence Theorem. The parameter controlling the change in the gauge connection is the inverse $\lambda$ of the topological mass. The BRST differential associated with the gauge connection redefinition is derived and the corresponding Slavnov-Taylor (ST) identities are proven to be anomaly-free. The Green functions of local operators constructed only from the ($\lambda$-dependent) transformed gauge connection, as well as those of BRST invariant operators, are shown to be independent of the parameter $\lambda$, as a consequence of the validity of the ST identities. The relevance of the antighost-ghost fields, needed to take into account at the quantum level the Jacobian of the change in the gauge connection, is analyzed. Their role in the identification of the physical states of the model within conventional perturbative gauge theory is discussed.Comment: 19 pages, LATEX, to appear in Journal of High Energy Physic

Phenotypic heterogeneity in Hidradenitis Suppurativa (Acne Inversa): classification is an essential step toward personalized therapy

Awareness is increasing that there is phenotypic heterogeneity within the hidradenitis suppurativa (HS) disease spectrum. However, the few randomized HS trials that are available have not distinguished between the subtypes of the disease. In this issue, Canoui-Poitrine et al. used latent class (LC) analysis of the largest HS cohort described to date to generate three phenotypic subtypes. LC 1 correlates with "typical" European HS, mainly involving the axilla, groin, and, in women, the inframammary region. "Atypical" HS, which may be linked to γ-secretase gene mutations, was subdivided further into LC2 and LC3 subtypes

UV finiteness of 3D Yang-Mills theories with a regulating mass in the Landau gauge

We prove that three-dimensional Yang-Mills theories in the Landau gauge supplemented with a infrared regulating, parity preserving mass term are ultraviolet finite to all orders. We also extend this result to the Curci-Ferrari gauge.Comment: 6 page

Development of core outcome sets in hidradenitis suppurativa:a systematic review of outcome measure instruments to inform the process

Background The recent hidradenitis suppurativa (HS) Cochrane review identified outcome measure heterogeneity as an important issue to address when designing future HS trials. Objectives To follow the Harmonising Outcome Measures for Eczema (HOME) roadmap, by performing a systematic review of HS outcome measure instruments to inform the development of a HS core outcome set. Methods We performed a systematic review to identify validation evidence for outcome measure instruments used in HS randomised controlled trials (RCTs), and assessed the methodological quality of all HS outcome measure validity studies using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist. Results The 12 RCTs included in the HS Cochrane review utilised a total of 30 outcome measure instruments, including 16 physician reported instruments, 11 patient reported instruments and three composite measures containing elements of both. Twenty-seven (90%) of the instruments lacked any validation data. Two further instruments have been developed and partially validated recently. Of the seven studies meeting our systematic review inclusion criteria, six were of ‘fair’ or ‘poor’ methodological quality, in part because most of the studies were not primarily designed for instrument validation. The HiSCR instrument is supported by good quality validation data but there are gaps including assessment of internal consistency, inter-rater reliability and minimal clinically important difference, and convergent validity fell below the acceptable range for some comparisons. Conclusions Multiple, usually unvalidated outcome measure instruments have been used in HS RCTs. Where validation evidence is available there are issues of low methodological quality or incomplete validity assessment and so no instruments can be fully recommended currently

Study of the Gribov region in Euclidean Yang-Mills theories in the maximal Abelian gauge

The properties of the Gribov region in SU(2) Euclidean Yang-Mills theories in the maximal Abelian gauge are investigated. This region turns out to be bounded in all off-diagonal directions, while it is unbounded along the diagonal one. The soft breaking of the BRST invariance due to the restriction of the domain of integration in the path integral to the Gribov region is scrutinized. Owing to the unboundedness in the diagonal direction, the invariance with respect to Abelian transformations is preserved, a property which is at the origin of the local U(1) Ward identity of the maximal Abelian gauge.Comment: 15 pages, one reference added, version accepted for publication in Phys. Rev.

On the symmetries of BF models and their relation with gravity

The perturbative finiteness of various topological models (e.g. BF models) has its origin in an extra symmetry of the gauge-fixed action, the so-called vector supersymmetry. Since an invariance of this type also exists for gravity and since gravity is closely related to certain BF models, vector supersymmetry should also be useful for tackling various aspects of quantum gravity. With this motivation and goal in mind, we first extend vector supersymmetry of BF models to generic manifolds by incorporating it into the BRST symmetry within the Batalin-Vilkovisky framework. Thereafter, we address the relationship between gravity and BF models, in particular for three-dimensional space-time.Comment: 29 page

Canonical Analysis of the Jackiw-Teitelboim Model in the Temporal Gauge. I. The Classical Theory

As a preparation for its quantization in the loop formalism, the 2-dimensional gravitation model of Jackiw and Teitelboim is analysed in the classical canonical formalism. The dynamics is of pure constraints as it is well-known. A partial gauge fixing of the temporal type being performed, the resulting second class constraints are sorted out and the corresponding Dirac bracket algebra is worked out. Dirac observables of this classical theory are then calculated.Comment: 15 pages, Latex. Misprint correction

The gluon and ghost propagators in Euclidean Yang-Mills theory in the maximal Abelian gauge: taking into account the effects of the Gribov copies and of the dimension two condensates

The infrared behavior of the gluon and ghost propagators is studied in SU(2) Euclidean Yang-Mills theory in the maximal Abelian gauge within the Gribov-Zwanziger framework. The nonperturbative effects associated with the Gribov copies and with the dimension two condensates are simultaneously encoded into a local and renormalizable Lagrangian. The resulting behavior turns out to be in good agreement with the lattice data.Comment: final version, to appear in Physical Review

The SU(2) X U(1) Electroweak Model based on the Nonlinearly Realized Gauge Group

The electroweak model is formulated on the nonlinearly realized gauge group SU(2) X U(1). This implies that in perturbation theory no Higgs field is present. The paper provides the effective action at the tree level, the Slavnov Taylor identity (necessary for the proof of unitarity), the local functional equation (used for the control of the amplitudes involving the Goldstone bosons) and the subtraction procedure (nonstandard, since the theory is not power-counting renormalizable). Particular attention is devoted to the number of independent parameters relevant for the vector mesons; in fact there is the possibility of introducing two mass parameters. With this choice the relation between the ratio of the intermediate vector meson masses and the Weinberg angle depends on an extra free parameter. We briefly outline a method for dealing with \gamma_5 in dimensional regularization. The model is formulated in the Landau gauge for sake of simplicity and conciseness: the QED Ward identity has a simple and intriguing form.Comment: 19 pages, final version published by Int. J. Mod. Phys. A, some typos corrected in eqs.(1) and (41). The errors have a pure editing origin. Therefore they do not affect the content of the pape