Article featured in New Scientist
The article "Knotty inflation and the dimensionality of spacetime", co-authored by Gr@v member João Rosa, was recently featured in the popular science magazine New Scientist, with comments by Prof. Alan Guth.
Cosmology News & Events
At MG14
Gr@v team at the 14th Marcel Grossmann Meeting, in Rome: (from left to right) M. Wang, H. Rúnarsson, J. C. Degollado (former member), E. Radu, C. Herdeiro, M. Sampaio and J. Rosa, where we have presented ten talks on the various group's research lines.
Under Rome's July hot sun, this workshop could be described modifying Edison's quote: "Science can really be 99% perspiration..."
Black-hole spins as gravitational and cosmological probes
Speaker
Enrico Barausse (Institut Astrophysique de Paris/CNRS)
Event date
Venue
GAP room
Event type
Abstract: I will discuss the relevance of the spins of massive black holes as probes of the coevolution of these objects with their host galaxies, as well as for the dynamics of binary systems and accretion disks, and for gravitational-wave emission. I will also present a semi-analytical model for the cosmological evolution of the spins of the massive black-hole population, and show that comparison of this model to existing spin measurements from relativistic iron lines allows one to put constraints on competing accretion scenarios. I will also comment on the prospects to test this model using future gravitational-wave space-based detectors.
Sociedade Portuguesa de Relatividade e Gravitação (SPRG)
2015 marks the centennial of the General Theory of Relativity (GR), presented by Albert Einstein in 1915. Motivated by this celebration, understanding that GR is an important part of the scientific world heritage and recognizing the growing international influence of Portuguese researchers working in this area, the "Portuguese Society of Relativity and Gravitation" (SPRG) was formally established in 2015.
Dynamics of Robertson-Walker spacetimes with diffusion
Speaker
Artur Alho (CAMGSD - IST)
Event date
Venue
GAP room
Event type
Abstract: We study the dynamics of spatially homogeneous and isotropic spacetimes containing a fluid undergoing microscopic velocity diffusion in a cosmological scalar field. After deriving a few exact solutions of the equations, we continue by analyzing the qualitative behavior of general solutions. To this purpose we recast the equations in the form of a two dimensional dynamical system and perform a global analysis of the flow. Among the admissible behaviors, we find solutions that are asymptotically de-Sitter both in the past and future time direction and which undergo accelerated expansion at all times.
Interview to Porto Canal
C. Herdeiro was the guest interviewee of Porto Canal's "Mentes que Brilham". Watch and listen to the conversation with interviewer Cláudia Fonseca about black holes and some of the research work made at Gr@v in this area.
Antonio Morais
Full Name: António de Aguiar e Pestana de Morais
Evidence for primordial gravitational waves from the BICEP2 experiment
Speaker
Joao Rosa
Event date
Venue
GAP room
Event type
IBERICOS 2014
Event date
Venue
Physics Amphitheatre
Ends on
Event Website
Event type
The IX Iberian Cosmology Meeting took place in Aveiro, Portugal, at the Physics Department of the University of Aveiro, from the 28th to the 30th of April 2014. This series of meetings is aimed at encouraging the interaction and collaboration between researchers working in Cosmology and related areas (Gravitation, Particle Physics and Astronomy) in Portugal and Spain. Researchers working in other countries will also be most welcome.
Curvature perturbation in multi-field inflation models with non-minimal coupling
Speaker
Masato Minamitsuji (IST, Lisbon)
Event date
Venue
GAP room
Event type
Abstract: Recent observations of the Cosmic Microwave Background (CMB) show very good consistency with an inflationary model with non-minimal coupling between the scalar and the inflaton field. Such a model is well motivated in the context of the unified theory, which also predicts the existence of many other scalar fields in addition to the inflaton.