### Conveners

#### Connection with Prof. Ruffini for greetings

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#### Connection with Prof. Ruffini for greetings

- Yu Wang ()

#### Connection with Prof. Ruffini for greetings

- Yu Wang ()

Three years ago the Event Horizon Telescope collaboration presented the first image reconstruction around the shadow for the supermassive black hole in M87*. It gives an opportunity to evaluate the shadow size. Recently, the Event Horizon Telescope collaboration constrained parameters (“charges”) of spherical symmetrical metrics of black holes from an estimated allowed interval for shadow...

We derive a particular approximate solution of Einstein equations, describing the gravitational field of a mass distribution that slightly deviates from spherical symmetry. The deviation is described by means of a quadrupole parameter that is responsible for the appearance of a curvature singularity, which is not covered by a horizon. We investigate the motion of test particles in the...

I survey our current research addressing evolution of matter in the Universe: Origin of matter is the quark-gluon phase of primordial Universe. Matter components evolve, at first we see hadronic universe, later we encounter lepton e+e-pair period followed by neutrino-photon free streaming towards recombination, dark matter and dark energy emergence. I show in detail the disappearance of...

As neutron stars merge, very high nuclear densities are attained in the core. As the merged hyper neutron star collapses to form a black hole, it must inevitably pass through the transition from hadronic to a quark matter. Hence, the associated post-merger gravitational radiation could be used to probe properties of the quark-matter physics. In this talk, we analyze the evolution and...

Motivated by string theory and AdS/CFT correspondence, we investigate certain behavior of the shadow geometrical shapes of higher-dimensional charged black hole solution in Einstein-Horndeski-Maxwell theory. We apply the Hamilton-Jacobi method to analyze photon orbits around the black hole and use the formulation of geodesic equations by the Carter approach. The influence of extra dimensions...

While the ideal limit of magnetohydrodynamics is a convenient and effective framework to model astrophysical sources, there are, possibly, physical situations that do not fall within this approximation. We discuss, in a historical perspective, some (mostly existing) scattered ideas that extend this framework.