Related papers: Gravitational Wave Formation from the Collapse of …

We investigate the propagation of gravitational waves on a black hole background within the low energy effective field theory of gravity, where effects from heavy fields are captured by higher dimensional curvature operators. Depending on…

Gravitational waves (GWs) originating from cosmological sources offer direct insights into the physics of the primordial Universe, the fundamental nature of gravity, and the cosmic expansion of the Universe. In this review paper, we present…

We present a mechanism for long bursts of gravitational radiation from Kerr black holes surrounded by a torus. These systems are believed to form in core-collapse of massive stars in association with gamma-ray bursts. The torus catalyzes…

After a brief review of the Maxwell-like approach to gravity we consider the issue of the negative energy of gravitational field which is a consequence of the field approach to the phenomenon of gravitation. Due to the existence of the…

We investigate a new mechanism to create large curvature perturbations on small scales due to parameter resonance in a single-field inflationary model with a small periodic structure upon the potential. After reentering the horizon, the…

Motivated by some of the recent swampland conjectures, we study a model of dark energy, in which a quintessence axion slowly rolls in a steep potential due to its interactions with a U(1) or an SU(2) gauge field. The gauge fields produced…

Understanding gravitational collapse requires understanding how $\sim 10^{58}$ nucleons can be destroyed in $\sim 10^{-5}$ seconds. The recent proposal that the endpoint of gravitational collapse can be a "dark energy star" implies that the…

Motivated by the new heavy dark matter production mechanism from cosmic phase transition, we propose a novel mechanism for the generation of microscopic gravitational waves (GWs) during cosmological first-order phase transitions arising…

Over the next decade, third-generation interferometers and the space-based LISA mission will observe binaries in galactic centers involving supermassive black holes with millions of solar masses. More precise measurements of more extreme…

In this article, we study the tensor mode equation of perturbation in the presence of nonzero-Lambda as dark energy, the dynamic nature of which depends on the Hubble parameter H and/or its time derivative. Dark energy, according to the…

One of the most dominant energy budgets in the Universe is Dark Energy, which remains enigmatic since its existence was first claimed based on observations of late-time cosmic acceleration. We propose a new way of inferring the dark energy…

We consider gravitational collapse of a fluid sphere with torsion generated by spin, which forms a black hole. We use the Tolman metric and the Einstein$-$Cartan field equations with a relativistic spin fluid as a source. We show that…

In this paper we analyze in detail a rarely discussed question of gravity wave production from evaporating primordial black holes. These black holes emit gravitons which are, at classical level, registered as gravity waves. We use the…

These notes summarize basic concepts underlying numerical relativity and in particular the numerical modeling of black hole dynamics as a source of gravitational waves. Main topics are the 3+1 decomposition of general relativity, the…

We show that astrophysical gravitational waves can undergo an anomalous modulation when propagating through cosmic gauge field dark energy. A sufficiently strong effect, dependent on the gauge field energy density, would appear as a…

Gravitational collapse into a black hole has been extensively studied with classical sources. We develop a new formalism to simulate quantum fields forming a black hole. This formalism utilizes well-established techniques used for classical…

Gravitational-wave detectors on earth have detected gravitational waves from merging compact objects in the local Universe. In future we will detect gravitational waves from higher-redshift sources, which trace the high-redshift structure…

The infinite gravitational collapse of any supermassive stars should pass through an energy scale of the grand unified theory (GUT). After nucleon-decays, the supermassive star will convert nearly all its mass into energy, and produce the…

An exact energy expression for a physical black hole is derived by considering the escape of a photon from the black hole. The mass of the black hole within its horizon is found to be twice its mass as observed at infinity. This result is…

The present paper deals with the gravitational collapse of an inhomogeneous spherical star consisting of dust fluid in the background of dark energy components with linear equation of state. We discussed the development of apparent horizon…