4 papers
Early- and Late-Time Modifications to CDM: Implications for the Hubble Tension
Rahul Dhyani, Purba Mukherjee, Arindam Chatterjee +1
We investigate an extension of CDM in which a fraction of cold Dark Matter (DM) decays into invisible dark radiation (DR) around the radiation-matter equality epoch, together w…
Dimming of Photon Ring due to Photon-Axion Conversion around Kerr Black Holes
Rahul Dhyani, Sauvik Sen, Indrani Banerjee +2
We investigate photon-axion conversion in the vicinity of rotating Kerr black holes where strong gravity traps photons on near-circular trajectories, effectively enhancing the path…
Inertial Frame Dragging as a Probe to Differentiate Kerr-Newman Naked Singularities from Black Holes
Arindam Kumar Chatterjee, Parthapratim Pradhan
We study the spin precession of a test gyroscope attached to a stationary observer in Kerr-Newman spacetime to distinguish a naked singularity from a black hole. Extending earlier…
Energy Extraction and Particle Acceleration in String-Inspired Rotating Einstein-Maxwell-Dilaton-Axion Black Hole
Arindam Kumar Chatterjee
We study energy extraction and particle acceleration in the rotating Einstein-Maxwell-Dilaton-Axion (EMDA) black hole, focusing on the impact of dilaton hair on near-horiz…