Spanish and Portuguese Relativity Meeting

Session

Parallel session 8 (Black Holes II)

Jul 23, 2024, 4:30 PM

Conveners

Parallel session 8 (Black Holes II)

• Session convener: Cristiano Germani

89. The Galactic Center as a gravitational laboratory

Riccardo Della Monica

7/23/24, 4:30 PM

The centre of the Milky Way has been subject of an intense observational program throughout the last thirty years, leading to exhibit the existence of a point source supermassive object named Sagittarius A (Sgr A). While stars orbiting around it are accelerated by gravity up to speeds of 10.000 km/s, Sgr A* moves at less than 1 km/s. The kinematic properties of such stars, called S-stars,...

34. Relativistic effects on the orbits of the closest stars to the black hole at the center of the Galaxy

Karim Abd El Dayem

7/23/24, 4:45 PM

In this presentation, we investigate the detection of the spin and quadrupole moment of the black hole at the center of the galaxy called Sgr A. These parameters affect the astrometric and spectroscopic observations of stars in the close vicinity of the black hole (S stars). Here, we consider a collection of S stars as well as putative stars that are closer to Sgr A, and thus much more...

88. Primordial black hole formation from a nonspherical density profile with a misaligned deformation tensor

Chulmoon Yoo

7/23/24, 5:00 PM

We perform the numerical simulation of primordial black hole formation from a nonspherical profile of the initial curvature perturbation $\zeta$. We consider the background expanding universe filled with the perfect fluid with the linear equation of state $p=w\rho$ ($w=1/3$ or $1/5$), where $p$ and $\rho$ are the pressure and the energy density, respectively. The initial condition is set in a...

85. Critical gravitational collapse in elastic matter models

Diogo Luís Farinha Gomes da Silva (CENTRA - Instituto Superior Técnico)

7/23/24, 5:15 PM

Critical collapse in general relativity is a topic with a rich history. In the case of perfect fluids in spherical symmetry, the critical solution at the threshold of black hole formation is known to be continously self-similar, a property that allows to compute the critical exponent by using renormalization group techniques and solving a system of ODEs forming a boundary value problem. I will...

90. Twist-free axisymetric critical collapse of a complex scalar field

Krinio Marouda (Instituto Superior Técnico)

7/23/24, 5:30 PM

It has been thirty years since the breakthrough paper of M. Choptuik on critical phenomena in the gravitational collapse of a real massless scalar field in spherical symmetry. This celebrated paper led to a rich exploration of different extreme spacetimes in numerical relativity, which persistently question the weak cosmic censorship conjecture, contribute to our understanding of spacetime...