The Evolution of Cosmological Perturbations in f(R)-gravity

Orador: Sante Carloni (Instituto Superior Técnico). Data, hora e local: 27 de Outubro de 2015, às 11h30m na sala de reuniões do Departamento de Matemática. Resumo: Using the language of the 1+3 covariant approach I will construct a complete theory of the linear perturbations for f(R)-gravity. The evolution equations for the scalar perturbations derived in…

SRB measures for non uniform hyperbolic endomorphisms

Orador: Anderson Cruz (Universidade do Porto). Data, hora e local: 23 de Outubro de 2015, às 14h na sala de reuniões do Departamento de Matemática. Resumo: The concept of SRB measures arise in the 70’s with the works of Sinai, Ruelle and Bowen. They shown that for C^2 hyperbolic diffeomorphisms there exist a invariant probability…

Non-local gravity and cosmology from string field theory

Orador: Alexey S. Koshelev. Data, hora e local: 6 de Outubro de 2015, às 11h30m na sala de reuniões do Departamento de Matemática. Resumo: I will introduce and review non-local modifications of Einstein’s gravity based on the string field theory. Existing explicit analytic solutions will be discussed. Especially bouncing solutions and Starobinsky solution. A special…

Semi-classical string tunnelling

Orador: Sérgio Giardino. Data, hora e local: 29 de Setembro de 2015, às 11h30m na sala de reuniões do Departamento de Matemática. Resumo: We will discuss the use of the semi-classical method proposed by Minahan (hep-th/0209047) for studying the pulsating string. We use this method to quantize and calculate the tunnelling rate of the pulsating…

Some history of Latin squares in experiments

Oradora: R. A. Bailey (University of St Andrews and Queen Mary, University of London). Data, hora e local: 22 de Setembro de 2015, às 16h na sala de reuniões do Departamento de Matemática. Resumo: In the 1920s, R. A. Fisher recommended Latin squares for crop experiments. However, there is evidence of their much earlier use…

Geometric properties of generalized Struve functions

Orador: Nihat Yagmur (Department of Mathematics, Faculty of Arts and Sciences, Erzincan University). Data, hora e local: 8 de Setembro de 2015, das 14h30m às 15h30m na sala de reuniões do Departamento de Matemática. Resumo: In the present work our object is to establish some geometric properties (like univalence, starlikeness, convexity and close-to-convexity) for the…