相关论文: General Relativistic Shock-Waves Propagating at th…

This paper concerns the construction and analysis of a new family of exact general relativistic shock waves. The construction resolves the open problem of determining the expanding waves created behind a shock-wave explosion into a static…

The mathematics of general relativistic shock waves is introduced and considered in a cosmological context. In particular, an expanding Friedmann-Roberson-Walker metric is matched to a Tolman-Oppenheimer-Volkoff metric across a spherical…

We construct the simplest solution of the Einstein equations that incorporates a shock-wave into a standard Friedmann-Robertson-Walker metric whose equation of state accounts for the Hubble constant and the microwave background radiation…

The propagation speed of the gravitational wave in scalar--Einstein--Gauss-Bonnet (sEGB) gravity is generally different from that of light. Using differential equation conditions for the speed of gravitational waves to coincide with the…

We present general relativistic solutions for self-similar spherical perturbations in an expanding cosmological background of cold pressure-less gas. We focus on solutions having shock discontinuities propagating in the surrounding cold…

We consider Einstein's equations coupled to the Euler equations in plane symmetry, with compact spatial slices and constant mean curvature time. We show that for a wide variety of equations of state and a large class of initial data,…

We derive a fully relativistic, self-similar solution to describe the propagation of a shock along an exponentially decreasing atmosphere, in the limit of very large Lorentz factor. We solve the problem in planar symmetry and compute the…

For the strong gravitational wave model, an explicit transformation is obtained from a privileged coordinate system with a wave variable to a synchronous reference frame with separation of time and space variables. In a synchronous…

We first review some aspects of gravitational wave and the thermodynamic expression of Einstein field equations, these achieved conclusions allow people to think of Einstein's gravitational wave as a kind of sound wave in ordinary gas which…

Both electromagnetic shock-waves and gravitational waves propagate with the speed of light. If they carry significant energy-momentum, this will change the properties of the space-time they propagate through. This can be described in terms…

We investigate the run-up of a shock wave from inside to the surface of a perfect fluid star in equilibrium and bounded by vacuum. Near the surface we approximate the fluid motion as plane-symmetric and the gravitational field as constant.…

Propagation of the strong shock in the flat expanding Friedman universe is investigated using methods of dimension and similarity. Exact analytic solution of self-similar equations is obtained, determining dependences of the radius and…

Astrophysical explosions are accompanied by the propagation of a shock wave through an ambient medium. Depending on the mass and energy involved in the explosion, the shock velocity $V$ can be non-relativistic ($V \ll c$, where $c$ is the…

By applying Noether symmetry methods, analytic solutions are obtained for a generalized Einstein-scalar-Gauss-Bonnet model with a $\xi(\phi)f(G)$ component. Variation with respect to the metric, supplemented by small perturbations, produces…

We study the evolution of the ultra-relativistic shock wave in a plane-parallel atmosphere adjacent to a vacuum and the subsequent breakout phenomenon. When the density distribution has a power law with the distance from the surface, there…

We consider an Einstein-Maxwell action modified by the addition of three terms coupling the electromagnetic strength to the curvature tensor. The corresponding generalized Maxwell equations imply a variation of the speed of light in a…

We construct exact, entropy satisfying shock wave solutions of the Einstein equations for a perfect fluid which extend the Oppeheimer-Snyder (OS) model to the case of non-zero pressure, {\it inside the Black Hole}. These solutions put forth…

In this work, we examine the propagation of gravitational waves in cosmological and astrophysical spacetimes in the context of Einstein--Gauss-Bonnet gravity, in view of the GW170817 event. The perspective we approach the problem is to…

We study the asymptotic behaviour of solutions to the linear wave equation on cosmological spacetimes with Big Bang singularities and show that appropriately rescaled waves converge against a blow-up profile. Our class of spacetimes…

We construct a class of global exact solutions of the Einstein equations that extend the Oppeheimer-Snyder (OS) model to the case of non-zero pressure, {\em inside the Black Hole}, by incorporating a shock wave at the leading edge of the…