9,360 research outputs found
Renormalization group and triviality in noncompact lattice QED with light fermions
In the framework of noncompact lattice QED with light fermions, we derive the
functional dependence of the average energy per plaquette on the bare
parameters using block-spin Renormalization Group arguments and assuming that
the renormalized coupling vanishes. Our numerical results for this quantity in
and lattices show evidence for triviality in the weak coupling
phase and point to a non vanishing value for the renormalized coupling constant
in the strong coupling phase.Comment: 9 page
An approach to the teaching of music reading in the elementary grades
Thesis (Ed.M.)--Boston Universit
Diquark condensation in two colour QCD
Unquenched lattice SU(2) is studied at nonzero chemical potential in the
strong coupling limit. The topic of diquark condensation is addressed analyzing
the probability distribution function of the diquark condensate. We present
results at zero external source without using any potentially dangerous
extrapolation procedure. We find strong evidences for a (high density) second
order phase transition where a diquark condensate appears, and show
quantitative agreement of lattice calculations with low-energy effective
Lagrangian calculations.Comment: 9 pages, 6 figures, to be published in the proceedings of the
``International Workshop on Non-Perturbative Methods and Lattice QCD'',
Guangzhou, China, 15-21 May 200
Global existence for reaction-diffusion evolution equations driven by the p-Laplacian on manifolds
We consider reaction-diffusion equations driven by the p-Laplacian on noncompact, infinite volume manifolds assumed to support the Sobolev inequality and, in some cases, to have L2 spectrum bounded away from zero, the main example we have in mind being the hyperbolic space of any dimension. It is shown that, under appropriate conditions on the parameters involved and smallness conditions on the initial data, global in time solutions exist and suitable smoothing effects, namely explicit bounds on the L∞ norm of solutions at all positive times, in terms of Lq norms of the data. The geometric setting discussed here requires significant modifications w.r.t. the Euclidean strategies
Blow-up versus global existence of solutions for reaction-diffusion equations on classes of Riemannian manifolds
It is well known from the work of Bandle et al. (J Differ Equ 251:2143-2163, 2011) that the Fujita phenomenon for reaction-diffusion evolution equations with power nonlinearities does not occur on the hyperbolic space H-N, thus marking a striking difference with the Euclidean situation. We show that, on classes of manifolds in which the bottom lambda of the L-2 spectrum of -delta is strictly positive (the hyperbolic space being thus included), a different version of the Fujita phenomenon occurs for other kinds of nonlinearities, in which the role of the critical Fujita exponent in the Euclidean case is taken by lambda. Such nonlinearities are time-independent, in contrast to the ones studied in Bandle et al. (2011). As a consequence of our results we show that, on a class of manifolds much larger than the case M = H-N considered in Bandle et al. (2011), solutions to (1.1) with power nonlinearity f(u) = u(p), p > 1, and corresponding to sufficiently small data, are global in time. Though qualitative similarities with similar problems in bounded, Euclidean domains can be seen in the results, the methods are significantly different because of noncompact setting dealt with
Association between one-hour post-load plasma glucose levels and vascular stiffness in essential hypertension
Objectives: Pulse wave velocity (PWV) is a surrogate end-point for cardiovascular morbidity and mortality. A plasma glucose
value 155 mg/dl (NGT155 had a worse insulin sensitivity and higher hs-CRP than NGT,155, similar to IGT subjects. In addition, NGT 155 subjects, compared with NGT,155, have higher PWV and its hemodynamic correlates
that increase their cardiovascular risk profile
Strongly Coupled QCD at Finite Baryon Density
The analytical results obtained in the infinite mass and strong coupling
limits of QCD are difficult to reconcile with the predictions of the Monomer
Dimer Polymer algorithm. We have reconsidered in detail the results obtained
with this simulation scheme and evidences of severe convergence problems are
presented for the SU(3) and SU(2) gauge group.Comment: LATTICE99(Finite Temperature and Density), 3 pages, 3 postscript
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