299 citations · 428 across the 18 of their papers we have counts for
19 papers
Metastable Dark Energy on the Phantom Brane
Purba Mukherjee, Arman Shafieloo, Varun Sahni +1
Recent DESI observations hint at a preference for dynamical dark energy with an equation of state (EoS) that crosses the phantom divide at . In this work, we investigate \tex…
Revisiting Metastable Dark Energy in Light of DESI DR2 BAO and DESI DR1 Full-Shape Measurements
Purba Mukherjee, Arman Shafieloo, Varun Sahni
We revisit metastable dark energy (DE) models described by a radioactive-like decay law. We consider three scenarios: an effective, exponentially decaying DE component; decay of DE…
Model-Independent Indication for a Localized Anomaly in the Late-Time Expansion History
Shibendu Gupta Choudhury, Purba Mukherjee, Eleonora Di Valentino +1
We investigate the late-time expansion history of the Universe using a model-independent spline reconstruction of cosmological distances based on the latest DESI DR2 baryon acousti…
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 wi…
Investigating the Tension and Expansion-History Mismatch with Diverse Dark Energy Parametrization Frameworks
Upala Mukhopadhyay, Purba Mukherjee, Alexandre Tkatchenko
In this work, we investigate whether the mismatch between early- and late-Universe inferences of the cosmic expansion history is associated with a particular redshift range, and wh…
Probing Interacting Dark Sectors with upcoming Post-Reionization and Galaxy Surveys
Rahul Shah, Antara Dey, Purba Mukherjee +1
We investigate the constraining power of future post-reionization and galaxy surveys on possible interactions between dynamical dark energy and dark matter. The analysis focuses on…
Exploring the Impact of Systematic Bias in Type Ia Supernova Cosmology Across Diverse Dark Energy Parametrizations
Drishti Sharma, Purba Mukherjee, Anjan A Sen +1
We investigate the impact of instrumental and astrophysical systematics on dark energy (DE) constraints from Type Ia supernova (SN-Ia) observations. Using simulated datasets consis…
Anchoring the Universe with Characteristic Redshifts using Raychaudhuri Equation Informed Reconstruction Algorithm (REIRA)
Shibendu Gupta Choudhury, Purba Mukherjee, Anjan Ananda Sen
We study the robustness and physical implications of a set of characteristic redshifts that capture key features of the late-time Universe. Using both model-independent reconstruct…
Can an Anti-de Sitter Vacuum in the Dark Energy Sector Explain JWST High-Redshift Galaxy and Reionization Observations?
Anirban Chakraborty, Tirthankar Roy Choudhury, Anjan Ananda Sen +1
The unexpectedly large abundance of UV-bright galaxies at discovered by the James Webb Space Telescope poses a significant challenge to the standard CDM cosmology. This w…
New Expansion Rate Anomalies at Characteristic Redshifts Geometrically Determined using DESI-DR2 BAO and DES-SN5YR Observations
Purba Mukherjee, Anjan A Sen
We perform a model-independent reconstruction of the cosmic distances using the Multi-Task Gaussian Process (MTGP) framework as well as knot-based spline techniques with DESI-DR2 B…
The CosmoVerse White Paper: Addressing observational tensions in cosmology with systematics and fundamental physics
Eleonora Di Valentino, Jackson Levi Said, Adam Riess +533
The standard model of cosmology has provided a good phenomenological description of a wide range of observations both at astrophysical and cosmological scales for several decades.…
A New Tension at Characteristic Redshift from DESI-DR1 BAO and DES-SN5YR Observations
Purba Mukherjee, Anjan A Sen
We perform a model-independent reconstruction of the angular diameter distance () using the Multi-Task Gaussian Process (MTGP) framework with DESI-DR1 BAO and DES-SN5YR data…
Towards a Composite Framework for Simultaneous Exploration of New Physics in Background and Perturbed Universe
Shibendu Gupta Choudhury, Purba Mukherjee, Anjan Ananda Sen
We investigate deviations from CDM by independently parameterizing modifications in the background evolution and the growth of structures. The background is characterized by two…
Model-Agnostic Cosmological Inference with SDSS-IV eBOSS: Simultaneous Probing for Background and Perturbed Universe
Purba Mukherjee, Anjan A. Sen
Here we explore certain subtle features imprinted in data from the completed Sloan Digital Sky Survey IV (SDSS-IV) extended Baryon Oscillation Spectroscopic Survey (eBOSS) as a com…
Quintessential Implications of the presence of AdS in the Dark Energy sector
Purba Mukherjee, Dharmendra Kumar, Anjan A Sen
We explore the implications for an Anti-de Sitter (AdS) vacuum, equivalently a negative cosmological constant (nCC), in the dark energy (DE) sector using current cosmological obser…
Model-independent calibration of Gamma-Ray Bursts with neural networks
Purba Mukherjee, Maria Giovanna Dainotti, Konstantinos F. Dialektopoulos +2
The Cold Dark Matter (CDM) cosmological model has been highly successful in predicting cosmic structure and evolution, yet recent precision measurements have highlighted dis…
Non-parametric reconstruction of cosmological observables using Gaussian Processes Regression
José de Jesús Velázquez, Luis A. Escamilla, Purba Mukherjee +1
The current accelerated expansion of the Universe remains ones of the most intriguing topics in modern cosmology, driving the search for innovative statistical techniques. Recent a…
Model-independent cosmological inference post DESI DR1 BAO measurements
Purba Mukherjee, Anjan Ananda Sen
In this work, we implement Gaussian process regression to reconstruct the expansion history of the universe in a model-agnostic manner, using the Pantheon-Plus SN-Ia compilation in…
A possible late-time transition of inferred via neural networks
Purba Mukherjee, Konstantinos F. Dialektopoulos, Jackson Levi Said +1
The strengthening of tensions in the cosmological parameters has led to a reconsideration of fundamental aspects of standard cosmology. The tension in the Hubble constant can also…