Related papers: Instability of exotic compact objects and its impl…
[abridged abstract] No, within a broad class of scenarios. With the advent of gravitational-wave (GW) astronomy, environmental effects on the GW signal will eventually have to be quantified. Here we present a wide survey of the corrections…
Astrophysical observations point toward strong evidence for the existence of black holes (BHs). Nevertheless, it is yet to be established or ruled out with confidence whether some exotic compact objects (ECOs), capable of mimicking black…
A Black Hole (BH) is a spacetime region with a horizon and where geodesics converge to a singularity. At such a point, the gravitational field equations fail. As an alternative to the problem of the singularity arises the existence of…
A number of theoretical proposals have been made for horizonless compact objects with masses and spins similar to those of black holes. While gravitational wave signatures from their mergers can resemble those of black holes, features like…
We investigate gravitational wave emission from an oscillating star modeled in a static Weyl background using a modulated waveform ansatz. First, we revisit the Weyl metric and obtain a Bessel-type curvature solution with regularity and…
New theoretical approaches developed in the last years predict that macroscopic quantum gravity effects in black holes should lead to modifications of the gravitational wave signals expected in the framework of classical general relativity,…
We consider a very simple model for gravitational wave echoes from black hole merger ringdowns which may arise from local Lorentz symmetry violations that modify graviton dispersion relations. If the corrections are sufficiently soft so…
The horizon of a classical black hole (BH), functioning as a one-way membrane, plays a vital role in the dynamic evolution of binary BHs, capable of absorbing fluxes entirely. Tidal heating, stemming from this phenomenon, exerts a notable…
Gravitational wave echoes can be used as a significant observable to understand the properties of black holes horizon. In addition, echoes would also closely relate to the unique properties of compact objects. In this work we study the…
It has been speculated that quantum gravity corrections may lead to modifications to space-time geometry near black hole horizons. Such structures may cause reflections to gravitational waves, causing {\it echoes} that follow the main…
We examine the main properties of gravitational waves (GWs) emitted by transient hyperbolic encounters of black holes. We begin by building the set of basic variables most relevant to setting our problem. After exposing the ranges of masses…
Gravitational wave astronomy might allow us to detect the coalescence of low-brightness astrophysical compact objects which are extremely difficult to be observed with current electromagnetic telescopes. Besides classical sources like black…
Some quantum-gravity theories suggest that the absorbing horizon of a classical black hole should be replaced by a reflective surface which is located a microscopic distance above the would-be classical horizon. Instead of an absorbing…
Gravitational waves from compact objects provide information about their structure, probing deep into strong-gravity regions. Here we illustrate how the presence or absence of an event horizon can produce qualitative differences in the…
We briefly consider the data of collaboration LIGO/VIRGO for gravitational waves (GW) and the recent observations of Event Horizon Telescope (EHT), and we discuss difficulties for finding the right theory of gravity and the nature of the…
Dark matter could be composed of compact dark objects (CDOs). A close binary of CDOs orbiting in the interior of solar system bodies can be a loud source of gravitational waves (GWs) for the LIGO and VIRGO detectors. We perform the first…
It has recently been reported by Cresswell et al. [1] that correlations in the noise surrounding the observed gravitational wave signals, GW150194, GW151226, and GW170194 were found by the two LIGO detectors in Hanford and Livingston with…
Quantum gravitational effects on the near horizon may alter the black hole's horizon drastically to be partially reflective, portrayed by a quantum membrane. With this modification, the object can be considered as an exotic compact object…
Exotic compact objects, horizonless spacetimes with reflective properties, have intriguingly been suggested by some quantum-gravity models as alternatives to classical black-hole spacetimes. A remarkable feature of spinning horizonless…
A compact object with a mass $\mathcal{O}(1 \sim 1000) M_{\odot}$, such as a black hole of stellar or primordial origin or a neutron star, and a much lighter exotic compact object with a subsolar mass could form a non-standard mini extreme…