On the Stability of Fundamental Couplings in the Galaxy

Astrophysical tests of the stability of Nature's fundamental couplings are a key probe of the standard paradigms in fundamental physics and cosmology. In this report we discuss updated constraints on the stability of the fine-structure constant $\alpha$ and the proton-to-electron mass ratio $\mu=m_p/m_e$ within the Galaxy. We revisit and improve upon the analysis by Truppe {\it et al.} by allowing for the possibility of simultaneous variations of both couplings and also by combining them with the recent measurements by Levshakov {\it et al.} By considering representative unification scenarios we find no evidence for variations of $\alpha$ at the 0.4 ppm level, and of $\mu$ at the 0.6 ppm level; if one uses the Levshakov bound on $\mu$ as a prior, the$\alpha$ bound is improved to 0.1 ppm. We also highlight how these measurements can constrain (and discriminate among) several fundamental physics paradigms.Comment: 7 pages, 1 figur

Effect of bulk viscosity on Elliptic Flow near QCD phase transition

Effects of the bulk viscosity on the elliptic flow are studied. To introduce a realistic equation of state and transport coefficients, we apply the results of the lattice QCD and hadron resonance gas calculations for these quantities. We found that the bulk viscosity acts in a non trivial manner on the elliptic flow $v_{2}$. The reduction of $v_{2}$ is more effective at low $p_{T}$ compared to the case of shear viscosity, whereas at high $p_{T}$, the situation is reversed, leading to $v_{2}$ enhancement. We argue that this is caused by the competition of the critical behaviors of the equation of state and the transport coefficients. We further found that Grad's method with the 14 moments approximation is not applicable to estimate the viscous effects for the one-particle distribution function at the freeze out.Comment: 14 pages, 12 figure

Dark Viscous Fluid coupled with Dark Matter and future singularity

We study effects of viscous fluid coupled with dark matter in our universe. We consider bulk viscosity in the cosmic fluid and we suppose the existence of a coupling between fluid and dark matter, in order to reproduce a stable de Sitter universe protected against future-time singularities. More general inhomogeneous fluids are studied related to future singularities.Comment: 11 page

A Generalization of Martin's Axiom

We define the $\aleph_{1.5}$ chain condition. The corresponding forcing axiom is a generalization of Martin's Axiom and implies certain uniform failures of club--guessing on $\omega_1$ that don't seem to have been considered in the literature before.Comment: 36 page

Teores de metanol em aguardentes vínicas e bagaceiras portuguesas

Comunicação apresentada no 8.º Simpósio de Vitivinicultura do Alentejo que decorreu em Évora de 5 a 7 de Maio de 2010.O metanol é um álcool resultante da degradação das pectinas que ocorre durante o processo de fermentação do vinho e do bagaço, passando para a aguardente durante o processo de destilação. A tecnologia utilizada na preparação dos vinhos e dos bagaços condiciona o seu teor nos destilados. Por razões de toxicidade, o teor de metanol nas aguardentes é limitado a 1000g/hL de álcool puro nas aguardentes bagaceiras e 200g/hL nas aguardentes vínicas (Reg. CE. 110/2008). Assim, antes da colocação das aguardentes no mercado deve ser avaliado o teor deste álcool, o qual é normalmente quantificado por cromatografia-gáslíquido de alta resolução. Neste trabalho são apresentados os teores de metanol de um número considerável de amostras analisadas no nosso laboratório, em 2007, 2008 e 2009. Os resultados obtidos mostram que nenhuma das amostras de aguardente vínica analisada apresentou um teor superior ao limite legal estabelecido. No caso das aguardentes bagaceiras, apenas quatro das amostras analisadas apresentaram teores acima do limite legal

Finite Temperature Phase Diagram of Quasi-Two-Dimensional Imbalanced Fermi Gases Beyond Mean-Field

We investigate the superfluid transition temperature of quasi-two-dimensional imbalanced Fermi gases beyond the mean-field approximation, through the second-order (or induced) interaction effects. For a balanced Fermi system the transition temperature is suppressed by a factor $\approx 2.72$. For imbalanced Fermi systems, the polarization and transition temperature of the tricritical point are significantly reduced as the two-body binding energy $|\epsilon_B|$ increases.Comment: 6 pages, 3 figure

Coeficiente de determinação genotípica em acessos de camucamuzeiro ( Myrciaria dúbia (H. B. K.) Mc. Vaugh).

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