12 papers
Primordial black hole in Lorentz-violating theories: Insights from Bumblebee gravity
Mohsen Khodadi, Javad T. Firouzjaee
The Bumblebee gravity (BG) model, featuring spontaneous Lorentz symmetry breaking via a vector field non-minimally coupled to curvature, has been widely used to explore Lorentz-vio…
Fragility of stealth solutions in mimetic gravity
Alireza Allahyari, Clarisse Donio, Mohammad Ali Gorji +2
We study a broad class of constrained mimetic-type extensions of general relativity with action , where …
When Dark Energy Turns On: Constraints on a Critical Emergence Model
Mahdi Najafi, Mahdi Habibollahi, Masoume Reyhani +4
We investigate a specific emergent dark energy scenario, known as critically emergent dark energy (CEDE), in which dark energy is effectively absent in the early Universe and becom…
Primordial observables of explicit diffeomorphism violation in gravity
Mohsen Khodadi, Nils A. Nilsson, Gaetano Lambiase +1
We investigate the potential for current and future gravitational-wave detectors to observe imprints of explicit diffeomorphism violation in primordial signals. Starting from a sim…
Reduced-order autoregressive dynamics of a complex financial system: a PCA-based approach
Pouriya Khalilian, Sara Azizi, Mohammad Hossein Amiri +1
This study analyzes the dynamic interactions among the NASDAQ index, crude oil, gold, and the US dollar using a reduced-order modeling approach. Time-delay embedding and principal…
A Multi-Probe ISW Study of Dark Energy Models with Negative Energy Density: Galaxy Correlations, Lensing Bispectrum, and Planck ISW-Lensing Likelihood
Payam Ghafari, Mahdi Najafi, Mina Ghodsi Yengejeh +3
We investigate the late-time imprints of three dark energy (DE) models, namely, the Chevallier-Polarski-Linder (CPL) parametrization, CDM, and an Omnipotent DE model, o…