Astrophysics News & Events

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Dynamical descalarization with a jump during black hole merger

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Speaker
Daniela Doneva (University of Tübingen)
Event date
Venue
Online (only) - Please, note the unusual time
Event type

The black hole merger in scalar-Gauss-Bonnet gravity can lead to dynamical descalarization this is a spontaneous release of the scalar
hair of the newly formed black hole. Depending on the exact form of the Gauss-Bonnet coupling function, the stable scalarized solutions

Constraints on dark matter from observations of neutron stars and their mergers

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Speaker
Violetta Sagun (University of Coimbra)
Event date
Venue
Hybrid Sala Sousa Pinto (Math dpt) and Zoom
Event type

Compact stars due to their enormous gravitational field can accumulate a sizable amount of dark matter in their interior. Depending on its nature, an accumulated dark matter may affect the properties of neutron stars in quite different ways. I will give an overview of the impact of dark matter on various observable properties of neutron stars, i.e.

Testing General Relativity with black hole X-ray data

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Speaker
Cosimo Bambi (Fudan University)
Event date
Venue
Online (only)
Event type

The theory of General Relativity has successfully passed a large number of observational tests. The theory has been extensively tested in the weak-field regime with experiments in the Solar System and observations of binary pulsars.

The fate of the light-ring instability

In the paper "The fate of the light-ring instability" Gr@v members P. Cunha, C. Herdeiro and E. Radu, together with former member, currently at the U. Valencia, N. Sanchis-Gual, have unveiled the mystery of the fate of a large class of horizonless ultracompact objects, that could be potential black hole foils.

 

 

A long standing intriguing possibility is if the astrophysical black hole candidates could be some other kind of mysterious objects but without event horizons, the defining property of black holes.

Gr@v joins EuCAPT

Gr@v is one of the 126 groups/institutions that joined the European Consortium for Astroparticle Theory (EuCAPT). EuCAPT purpose is to bring together theoretical cosmologists and astroparticle physicists across Europe aiming at increasing the exchange of ideas, coordinate scientific activities, help in the attraction of adequate resources as well as promoting a stimulating, fair and open environment in which young scientists can thrive. Gr@v's participation is coordinated by A. Morais.