Publications related to Semiclassical S-matrix for black holes

A generalization of the Hawking black hole area theorem

Hawking's black hole area theorem was proven using the null energy condition (NEC), a pointwise condition violated by quantum fields. The violation of the NEC is usually cited as the reason that black hole evaporation is allowed in the context of semiclass ...

Springer/Plenum Publishers2024

Resolving the vicinity of supermassive black holes with gravitational microlensing

Georgios Vernardos

Upcoming wide-field surveys will discover thousands of new strongly lensed quasars which will be monitored with unprecedented cadence by the Legacy Survey of Space and Time (LSST). Many of these quasars will undergo caustic-crossing events over the 10-yr L ...

Oxford Univ Press2024

Instability and trajectories of buoyancy-driven annular disks: A numerical study

François Gallaire, Pier Giuseppe Ledda, Giovanni Vagnoli

We investigate the stability of the steady vertical path and the emerging trajectories of a buoyancy -driven annular disk as the diameter of its central hole is varied. The steady and axisymmetric wake associated with the steady vertical path of the disk, ...

Amer Physical Soc2024

Accretion Disk Size and Updated Time-delay Measurements in the Gravitationally Lensed Quasar SDSS J165043.44+425149.3

Frédéric Courbin, Martin Raoul Robert Millon

We analyze variability in 15-season optical lightcurves from the doubly imaged lensed quasar SDSS J165043.44+425149.3 (SDSS1650), comprising five seasons of monitoring data from the Maidanak Observatory (277 nights in total, including the two seasons of da ...

Iop Publishing Ltd2024

Critical degeneracy in a nonlinear hyperbolic equation can produce atypical instability

Charles Stuart

This paper deals with the initial value problem for a semilinear wave equation on a bounded domain and solutions are required to vanish on the boundary of this domain. The essential feature of the situation considered here is that the ellipticity of the sp ...

2024

Tracing the rise of supermassive black holes A panchromatic search for faint, unobscured quasars at z ≥ 6 with COSMOS-Web and other surveys

Michaela Hirschmann

We report the identification of 64 new candidates of compact galaxies, potentially hosting faint quasars with bolometric luminosities of L-bol = 10(43)-10(46) erg s(-1), residing in the reionization epoch within the redshift range of 6 less than or similar ...

Edp Sciences S A2024

The Origins of Gas Accreted by Supermassive Black Holes: The Importance of Recycled Gas

Michaela Hirschmann

We investigate the fueling mechanisms of supermassive black holes (SMBHs) by analyzing 10 zoom-in cosmological simulations of massive galaxies, with stellar masses 1011-12 M circle dot and SMBH masses 108.9-9.7 M circle dot at z = 0, featuring various majo ...

Iop Publishing Ltd2024

Primordial black hole isocurvature modes from non-Gaussianity

Primordial black holes (PBHs) are black holes that might have formed in high density regions in the early universe. The presence of local-type non-Gaussianity can lead to large-scale fluctuations in the PBH formation rate. If PBHs make up a non-negligible ...

IOP Publishing Ltd2023

Strong gravitational lensing by AGNs as a probe of the quasar-host relations in the distant Universe

Malte Tewes, Frédéric Courbin, Martin Raoul Robert Millon, Aymeric Alexandre Galan

A rare case of a quasar acting as a gravitational lens allows a precise determination of the mass of the quasar's host galaxy and offers a new path to studying the connections between supermassive black holes and their host galaxies. ...

NATURE PORTFOLIO2023

Probing compact dark matter objects with microlensing in gravitationally lensed quasars

Frédéric Courbin, Martin Raoul Robert Millon, Eric Gérard Guy Paic, Hung-Hsu Chan, Petra Awad

The microlensing signal in the light curves of gravitationally lensed quasars can shed light on the dark matter (DM) composition in their lensing galaxies. Here, we investigate a sample of six lensed quasars from the most recent and best COSMOGRAIL observa ...

EDP SCIENCES S A2023

COSMOS-Web: An Overview of the JWST Cosmic Origins Survey

Richard Massey, Michaela Hirschmann

We present the survey design, implementation, and outlook for COSMOS-Web, a 255 hr treasury program conducted by the James Webb Space Telescope in its first cycle of observations. COSMOS-Web is a contiguous 0.54 deg² NIRCam imaging survey in four filters ( ...

IOP Publishing Ltd2023

Hidden Little Monsters: Spectroscopic Identification of Low-mass, Broad-line AGNs at z> 5 with CEERS

Michaela Hirschmann

We report on the discovery of two low-luminosity, broad-line active galactic nuclei (AGNs) at z > 5 identified using JWST NIRSpec spectroscopy from the Cosmic Evolution Early Release Science (CEERS) survey. We detect broad Ha emission in the spectra of bot ...

Iop Publishing Ltd2023

CEERS Key Paper. VI. JWST/MIRI Uncovers a Large Population of Obscured AGN at High Redshifts

Michaela Hirschmann

Mid-infrared (mid-IR) observations are powerful in identifying heavily obscured active galactic nuclei (AGN) that have weak emission in other wavelengths. Data from the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope provides an exce ...

2023

Preserving the positivity of the deformation gradient determinant in intergrid interpolation by combining RBFs and SVD: Application to cardiac electromechanics

Alfio Quarteroni, Francesco Regazzoni

The accurate, robust and efficient transfer of the deformation gradient tensor between meshes of different resolution is crucial in cardiac electromechanics simulations. This paper presents a novel method that combines rescaled localized Radial Basis Funct ...

Elsevier Science Sa2023

Classical soft graviton theorem rewritten

Biswajit Sahoo

Classical soft graviton theorem gives the gravitational wave-form at future null infinity at late retarded time u for a general classical scattering. The large u expansion has three known universal terms: the constant term, the term proportional to 1/u and ...

Springer Nature2022

Covariant formulation of relativistic mechanics

Miguel Alexandre Ribeiro Correia

Accretion disks surrounding compact objects, and other environmental factors, deviate satellites from geodetic motion. Unfortunately, setting up the equations of motion for such relativistic trajectories is not as simple as in Newtonian mechanics. The prin ...

American Physical Society2022

A simple theoretical model for estimating the frequency characteristics of black hole mergers

Roberto Guarino

Gravitational waves, despite predicted within the Theory of General Relativity about a century ago, were observed experi-mentally only in the last few years, thanks to the recent advances of the LIGO and Virgo detectors. In this work, we introduce a simple ...

2022

Efficient lattice Green's function method for bounded domain problems

William Curtin, Max Ludwig Hodapp, Ankit Gupta

The lattice Green's function method (LGFM) is the discrete counterpart of the continuum boundary element method and is a natural approach for solving intrinsically discrete solid mechanics problems that arise in atomistic-continuum coupling methods. Here, ...

Wiley2022

TimeEvolver: A program for time evolution with improved error bound

Sebastian Zell

We present TimeEvolver, a program for computing time evolution in a generic quantum system. It relies on well-known Krylov subspace techniques to tackle the problem of multiplying the exponential of a large sparse matrix iH, where His the Hamiltonian, with ...

ELSEVIER2022

An Efficient Signal-to-noise Approximation for Eccentric Inspiraling Binaries

Alexandra Shelest

Eccentricity has emerged as a potentially useful tool for helping to identify the origin of black hole mergers. However, eccentric templates can be computationally very expensive owing to the large number of harmonics, making statistical analyses to distin ...

IOP Publishing Ltd2022