Physics / Stellar & Compact Objects
Stellar physics, compact objects, and high-energy astrophysical phenomena. Research spans black hole thermodynamics, stellar evolution, radiative processes, and accretion physics.
We review the current status of compact object simulations that are based on the Smoothed Particle Hydrodynamics (SPH) method. The first section of this review is dedicated to SPH as a numerical method for Newtonian, ideal gas dynamics and it should be fairly self-contained. It begins with the basic
X-ray reflection spectroscopy provides one of the most powerful electromagnetic methods for measuring the dimensionless spin of accreting black holes. It has yielded spin constraints for stellar-mass black holes in X-ray binaries and supermassive black holes in active galactic nuclei, and is central
Active galactic nuclei (AGN) feedback via black hole-driven jets and winds plays a key role in redistributing matter across megaparsec scales. However, the implementation of jet feedback in cosmological simulations remains highly prescriptive, leading to uncertainties in the predicted state of the W
In this study we introduce a new simulation campaign designed to understand how parameters that control star-formation and AGN feedback processes in cosmological hydrodynamical simulations impact observables such as the galaxy stellar-mass function (GSMF) and the gas fractions in large dark matter h
Many of the most luminous extragalactic transients originate from the accretion of material onto a black hole (BH) via core-collapse, stellar mergers, or the tidal disruption of a star. Some produce energetic multi-wavelength emission, displaying short, blue optical flares and bright, long-lived rad
The centre of mass (CoM) of compact binary coalescences (CBCs) occurring in the vicinity of a supermassive black hole, through interaction with an arbitrary third body (e.g., of stellar mass), or in a dense stellar environment, will undergo a time-varying line-of-sight (LOS) velocity. This in turn l
We report the X-ray and optical spectroscopic properties of TDE 2025aarm, the second closest tidal disruption event (TDE) discovered to date. The proximity of this source, combined with a deep and intense X-ray monitoring campaign spanning six months, allowed us to probe the source down to an unprec
SDSS J1548+2208 is a unique partially obscured nuclear transient that exhibits multiwavelength outbursts in mid-infrared, X-rays, and radio. We present the results from multiwavelength photometric and spectroscopic follow-up observations with a time span of ∼2500 days since its discovery. We find th
This study investigates the concept of “collective bricolage” within the framework of creating a universe science observatory in France. In the face of significant transformations in higher education and research, this article examines how university stakeholders can employ collective bricolage to a
This thesis investigates the underexplored role of music within early Coptic literature to address a significant gap in early Christian musicology. While substantial research has been conducted on Greek, Latin, and Syriac language sources (McKinnon, 1987; Page 2010), Coptic-language texts have been
Overview This dataset provides the results of a high-fidelity cosmological simulation exploring the non-linear dynamics of a universe dominated by Primordial Black Holes (PBHs). The simulation was executed on NVIDIA Blackwell (B200) hardware at a native resolution of $2560^3$ ($16.7$ billion voxels)
This supplement extends the dimensionless predictions of the main document to absolute mass scales and cosmological observables, addressing the dimensional transmutation problem. It bridges dimensionless topological predictions to physical mass scales in GeV.
This supplement extends the dimensionless predictions of the main document to absolute mass scales and cosmological observables, addressing the dimensional transmutation problem. It bridges dimensionless topological predictions to physical mass scales in GeV.
This work presents a rigorous mathematical formulation of cosmological mechanics within the Cosmological Thermosynthesis Theory v3.2 (TTC v3.2). The theory posits that spacetime and all fundamental interactions emerge from a primordial superfluid of ultralight scalar bosons termed etherions, with ma
The third paper in a four-paper series connecting FCC lattice cohomology, Apollonian circle packing, and post-quantum cryptography. Papers 1 and 2 proved that the FCC cycle space carries a natural V4 symmetry and that the FCC primitive cell is the symmetric Apollonian seed in R³’¹, with the directed
The philosopher Giorgio Agamben has argued that the ‘human/nonhuman distinction is the conceptual ground for any further ontological elaboration’, (Grieve-Carlson, 179) that humans must distinguish themselves from their environment and other beings before the work of culture can begin. However, obje