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20112025
most citedCosmological perturbations in mimetic Horndeski gravity

51 citations · 261 across the 14 of their papers we have counts for

collaborators

14 papers

gr-qc2025

Dynamical Dark Energy or Modified Gravity? Signatures in Gravitational Wave Propagation

Purnendu Karmakar, Sandeep Haridasu

We discuss the implications of the most recent DESI Baryon Acoustic Oscillations (BAO) DR2 and DESyr5 compilation of supernovae (SNe) datasets for modified gravity focusing on non-…

astro-ph.CO2025

Constraints on Logarithmic Model Extensions of Symmetric Teleparallel Gravity

Purnendu Karmakar, Sandeep Haridasu, Atsushi Nishizawa

We address various cosmological phenomenologies in the symmetric teleparallel framework both in background and perturbation such as cosmic expansion, gravitational coupling constan…

astro-ph.CO2021★ 5 cited

Generalised scalar-tensor theories of gravity and pressure profiles of galaxy clusters

Balakrishna S. Haridasu, Purnendu Karmakar, Marco De Petris +2

In the current proceedings, we summarise the results presented during the mm Universe@NIKA2 conference, taken from our main results in \cite{Haridasu:2021hzq}. We test the Degenera…

astro-ph.CO2021★ 8 cited

Testing generalized scalar-tensor theories of gravity with clusters of galaxies

Balakrishna S. Haridasu, Purnendu Karmakar, Marco De Petris +2

We test the generalized scalar-tensor theory in static systems, namely galaxy clusters. The Degenerate higher-order scalar-tensor (DHOST) theory modifies the Newtonian potential th…

astro-ph.CO2020★ 10 cited

Jointly fitting weak lensing, X-ray and Sunyaev-Zel'dovich data to constrain scalar-tensor theories with clusters of galaxies

Vincenzo F. Cardone, Purnendu Karmakar, Marco De Petris +1

Degenerate higher-order scalar-tensor (DHOST) theories are considered the most general class of scalar-tensor theories so that any constraints on them apply to the full set of scal…

gr-qc2019★ 15 cited

Cosmological evolution of viable models in the generalized scalar-tensor theory

Shun Arai, Purnendu Karmakar, Atsushi Nishizawa

We investigate the parameter distributions of the viable generalized scalar-tensor theory with conventional dust matter after GW170817 in a model-independent way. We numerically co…

gr-qc2018★ 40 cited

Hamiltonian analysis of mimetic scalar gravity revisited

Alexander Ganz, Purnendu Karmakar, Sabino Matarrese +1

We perform the Hamiltonian analysis of several mimetic gravity models and compare our results with those obtained previously by different authors. We verify that for healthy mimeti…

gr-qc2018★ 18 cited

Gravity in mimetic scalar-tensor theories after GW170817

Alexander Ganz, Nicola Bartolo, Purnendu Karmakar +1

We derive the most general mimetic scalar-tensor theory assuming a healthy "seed" action and accounting for the constraints on the speed of gravitational-wave propagation arising f…

gr-qc2017★ 20 cited

Cosmic structures and gravitational waves in ghost-free scalar-tensor theories of gravity

Nicola Bartolo, Purnendu Karmakar, Sabino Matarrese +1

We study cosmic structures in the quadratic Degenerate Higher Order Scalar Tensor (qDHOST) model, which has been proposed as the most general scalar-tensor theory (up to quadratic…

astro-ph.CO2017★ 17 cited

Large-scale structure in mimetic Horndeski gravity

Frederico Arroja, Teppei Okumura, Nicola Bartolo +2

In this paper, we propose to use the mimetic Horndeski model as a model for the dark universe. Both cold dark matter (CDM) and dark energy (DE) phenomena are described by a single…

gr-qc2015★ 51 cited

Cosmological perturbations in mimetic Horndeski gravity

Frederico Arroja, Nicola Bartolo, Purnendu Karmakar +1

We study linear scalar perturbations around a flat FLRW background in mimetic Horndeski gravity. In the absence of matter, we show that the Newtonian potential satisfies a second-o…

astro-ph.CO2011★ 38 cited

Cosmological Implications of Unimodular Gravity

Pankaj Jain, Atul Jaiswal, Purnendu Karmakar +2

We consider a model of gravity and matter fields which is invariant only under unimodular general coordinate transformations (GCT). The determinant of the metric is treated as a se…

gr-qc2011★ 32 cited

Testing Unimodular Gravity

Pankaj Jain, Purnendu Karmakar, Subhadip Mitra +2

We consider models of gravitation that are based on unimodular general coordinate transformations (GCT). These transformations include only those which do not change the determinan…

gr-qc2011★ 7 cited

Cosmological Perturbation Analysis in a Scale Invariant Model of Gravity

Pankaj Jain, Purnendu Karmakar, Subhadip Mitra +2

We consider a model for gravity that is invariant under global scale transformations. It includes one extra real scalar field coupled non-minimally to the gravity fields. In this m…