Smooth Bosonization II: The Massive Case

The (1+1)-dimensional bosonization relations for fermionic mass terms are derived by choosing a specific gauge in an enlarged gauge-invariant theory containing both fermionic and bosonic fields. The fermionic part of the generating functional subject to the gauge constraint can be cast into the form of a strongly coupled Schwinger model, which can be solved exactly. The resulting bosonic theory coupled to the scalar sources then exhibits directly the bosonic counterparts of the fermionic scalar and pseudoscalar mass densities.Comment: 8 pages, Latex, CERN-TH-6563/9

Vector field localization and negative tension branes

It is shown that negative tension branes in higher dimensions may lead to an effective lower dimensional theory where the gauge-invariant vector fields associated with the fluctuations of the metric are always massless and localized on the brane. Explicit five-dimensional examples of this phenomenon are provided. Furthermore, it is shown that higher dimensional gauge fields can also be localized on these configurations with the zero mode separated from the massive tower by a gap.Comment: 16 pages, LaTeX style; to appear in Phys. Rev.

Plausibility functions and exact frequentist inference

In the frequentist program, inferential methods with exact control on error rates are a primary focus. The standard approach, however, is to rely on asymptotic approximations, which may not be suitable. This paper presents a general framework for the construction of exact frequentist procedures based on plausibility functions. It is shown that the plausibility function-based tests and confidence regions have the desired frequentist properties in finite samples---no large-sample justification needed. An extension of the proposed method is also given for problems involving nuisance parameters. Examples demonstrate that the plausibility function-based method is both exact and efficient in a wide variety of problems.Comment: 21 pages, 5 figures, 3 table

Lattice Study of the Massive Schwinger Model with a θ\theta term under L\"uscher's "Admissibility" condition

We present a numerical study of the massive two-flavor QED in two dimensions with the gauge action proposed by L\"uscher, which allows only ``admissible'' gauge fields. We find that the admissibility condition does not allow any topology changes by the local updation in Hybrid Monte Carlo algorithm so that the configurations in each topological sector can be generated separately. By developing a new method to sum over different topological sectors, we investigate $\theta$ vacuum effects. Combining with domain-wall fermion action, we obtain the fermion mass dependence and $\theta$ dependence of the meson masses, which are consistent with the analytic results by mass perturbation in the continuum theory.Comment: 3 pages, Lattice2003(chiral

Produktorienteret miljøindsats i landbrugssektoren - forudsætninger

For at styrke den produktorienterede miljøindsats i landbruget nedsatte Miljøstyrelsen primo 2003 et produktkædepanel for landbrugsområdet. Panelets primære mål er at fremme udvikling og afsætning af landbrugsprodukter, der set i et livscyklusperspektiv ("fra jord til jord") er mindre miljøbelastende end tilsvarende traditionelle produkter. Som fundament for panelets arbejde er udarbejdet denne rapport, som beskriver de eksisterende forudsætninger for en produktorienteret indsats i sektoren - i form af en kortlægning af relevante projekter/tiltag. Denne rapport har dannet udgangspunkt for udarbejdelsen af et såkaldt fremsyn på området, som er publiceret særskilt. Fremsynet og information om panelets arbejde i øvrigt kan fås på www.produktpanel-landbrug.dk. En produktorienteret indsats vil altid være et supplement til de eksisterende overordnede reguleringer af samfundets adfærd, forbrug og udledninger. Vi vil stadig i fremtiden opleve berettiget miljøarbejde, der tager udgangspunkt i en konkret produktion eller proces eller i ønsket om at reducere en arealbelastning. Med produktorientering følger en anderledes og mere nuanceret opfattelse af, hvad der er "godt og dårligt" for miljøet, hvilke områder, der skal prioriteres i fødevaresektorens miljøindsats, og hvad miljøarbejdet kan omfatte i alle led i fødevarernes produktkæde. Et produktorienteret miljøarbejde stiller krav til og udfordrer alle aktører i produktkæderne. Der skal ikke alene udveksles og håndteres oplysninger om produktets miljøpåvirkning bagud og fremad i produktkæden, men der skal også ageres på baggrund af de erkendelser, denne udveksling af oplysninger giver anledning til. Helhedsorienteringen skaber også muligheder for at synliggøre og dokumentere valg undervejs i produktkæden. Produktorientering giver dermed en enestående mulighed for aktører/virksomheder for at dokumentere adfærd og valg overfor aftagere (herunder forbrugeren). Også for landbrugs- og gartnerierhvervet er produktorienteringen en udfordring. En kvalificeret diskussion af muligheder og perspektiver i produktorienteringen i landbrugserhvervet er derfor langt fra kun et spørgsmål om værktøjer, opgørelsesmetoder og mulighederne for afsætning af miljødokumenterede varer. Produktorienteringen er i langt højere grad den ramme, hvori f.eks. nedenstående spørgsmål kan diskuteres: Hvilke langsigtede scenarier for landbrugserhvervet er tænkelige? Hvilke strategier kan anlægges for erhvervsudvikling, forskning, kompetenceudvikling etc. for bedst muligt at sigte på de mest attraktive scenarier? Hvordan bringes aktørerne i spil, og hvordan skal ansvar fordeles? De hidtidige erfaringer med produktorientering viser, at en væsentlig forudsætning for succes er åbenhed og kommunikation i produktkæderne

Properties of the Fixed Point Lattice Dirac Operator in the Schwinger Model

We present a numerical study of the properties of the Fixed Point lattice Dirac operator in the Schwinger model. We verify the theoretical bounds on the spectrum, the existence of exact zero modes with definite chirality, and the Index Theorem. We show by explicit computation that it is possible to find an accurate approximation to the Fixed Point Dirac operator containing only very local couplings.Comment: 38 pages, LaTeX, 3 figures, uses style [epsfig], a few comments and relevant references adde

The Interplay Between the "Low" and "High" Energy CP-Violation in Leptogenesis

We analyse within the "flavoured" leptogenesis scenario of baryon asymmetry generation, the interplay of the "low energy" CP-violation, originating from the PMNS neutrino mixing matrix $U$, and the "high energy" CP-violation which can be present in the matrix of neutrino Yukawa couplings, $\lambda$, and can manifest itself only in "high" energy scale processes. The type I see-saw model with three heavy right-handed Majorana neutrinos having hierarchical spectrum is considered. The "orthogonal" parametrisation of the matrix of neutrino Yukawa couplings, which involves a complex orthogonal matrix $R$, is employed. In this approach the matrix $R$ is the source of "high energy" CP-violation. Results for normal hierarchical (NH) and inverted hierarchical (IH) light neutrino mass spectrum are derived in the case of decoupling of the heaviest RH Majorana neutrino. It is shown that taking into account the contribution to $Y_B$ due to the CP-violating phases in the neutrino mixing matrix $U$ can change drastically the predictions for $Y_B$, obtained assuming only "high energy" CP-violation from the $R$-matrix is operative in leptogenesis. In the case of IH spectrum, in particular, there exist significant regions in the corresponding parameter space where the purely "high energy" contribution in $Y_B$ plays a subdominant role in the production of baryon asymmetry compatible with the observations.Comment: Results unchanged; comments and references added; version to be puplished in Eur.Phys.J.

Radiative Corrections to Neutrino Mixing and CP Violation in the Minimal Seesaw Model with Leptogenesis

Radiative corrections to neutrino mixing and CP violation are analyzed in the minimal seesaw model with two heavy right-handed neutrinos. We find that textures of the effective Majorana neutrino mass matrix are essentially stable against renormalization effects. Taking account of the Frampton-Glashow-Yanagida ansatz for the Dirac neutrino Yukawa coupling matrix, we calculate the running effects of light neutrino masses, lepton flavor mixing angles and CP-violating phases for both $m_1 =0$ (normal mass hierarchy) and $m_3 =0$ (inverted mass hierarchy) cases in the standard model and in its minimal supersymmetric extension. Very instructive predictions for the cosmological baryon number asymmetry via thermal leptogenesis are also given with the help of low-energy neutrino mixing quantities.Comment: 21 pages, 6 figures; more references adde