Related papers: Testing Emergent Gravity with Isolated Dwarf Galax…
We propose a novel method to measure the $E_G$ statistic from clustering alone. The $E_G$ statistic provides an elegant way of testing the consistency of General Relativity by comparing the geometry of the Universe, probed through…
In modified gravity theories that seek to explain cosmic acceleration, dwarf galaxies in low density environments can be subject to enhanced forces. The class of scalar-tensor theories, which includes f(R) gravity, predict such a force…
Chameleon theories of gravity predict that the gaseous component of isolated dwarf galaxies rotates with a faster velocity than the stellar component. In this paper, we exploit this effect to obtain new constraints on the model parameters…
Emergent modified gravity presents a new set of generally covariant gravitational theories in which the space-time metric is not directly given by one of the fundamental fields. A metric compatible with the modified dynamics of gravity is…
To solve some problems of celestial mechanics and astrophysics, three new models of an elliptical galaxy (EG) have been created, which are in good agreement with modern understanding of the structure of such galaxies. Based on these models,…
For nearly a century, Einstein's theory of gravity has been the standard theory for describing gravitational phenomena in our universe. Along with its successes, limitations of the theory from theoretical (e.g., singularities) and…
New covariant theories of emergent modified gravity exist not only in spherically symmetric models, as previously found, but also in polarized Gowdy systems that have a local propagating degree of freedom. Several explicit versions are…
Isolated galaxies are rare yet invaluable for studying secular evolution, as their physical properties can remain largely unaffected by external influences for several billion years, primarily shaped by internal evolutionary processes. This…
The galaxy circular velocity function at small masses is related to the matter power spectrum on small scales. Although this function is well-studied for Local Group dwarfs, theoretical predictions and observational measurements are…
This review explores modified theories of gravity, particularly $f(R)$ gravity, as extensions to General Relativity (GR) that offer alternatives to dark energy for explaining cosmic acceleration. These models generalize the Einstein-Hilbert…
We present a list of 75 isolated late-type dwarf galaxies which have no neighbors with a relative radial velocity difference of less than 500 km/s or projected separations within 500 kpc. These were selected from $\sim$2000 dwarf galaxies…
In this PhD thesis I make use of the "Effective Field Theory of Gravity for Extended Objects" by Goldberger and Rothstein in order to investigate theories of gravity and to take a different point of view on the physical information that can…
We review recent progress in the construction of modified gravity models as alternatives to dark energy as well as the development of cosmological tests of gravity. Einstein's theory of General Relativity (GR) has been tested accurately…
In 2016, Erik Verlinde proposed a new theory of gravity called "emergent gravity" by using mathematical formulas used in the theory of elasticity. In 2017, De-Chang Dai and Dejan Stojkovic claimed to point out inconsistencies in Verlinde's…
$E_G$ is a summary statistic that combines cosmological observables to achieve a test of gravity that is relatively model-independent. Here, we consider the power of a measurement of $E_G$ using galaxy-galaxy lensing and galaxy clustering…
Higher-derivative gravity theories offer insights into the behavior of extremely compact objects (ECOs). Focusing on Gauss-Bonnet (GB) and Einstein-dilaton-Gauss-Bonnet (EdGB) gravity, we derive the compactness scale in these models and…
We present an analysis of the ENEAR sample of peculiar velocities of elliptical galaxies, obtained with D_n-\sigma distances. We use the velocity correlation function to analyze the statistics of the field-object's velocities, while the…
The flattening of spiral-galaxy rotation curves is unnatural in view of the expectations from Kepler's third law and a central mass. It is interesting, however, that the radius-independence velocity is what one expects in one less…
As an alternative gravitational theory to General Relativity (GR), the Conformal Gravity (CG) has recently been successfully verified by observations of Type Ia supernovae (SN Ia) and the rotation curves of spiral galaxies. The observations…
We use galaxy-galaxy weak lensing data to perform a novel test on general relativity (GR) and $f(T)$ torsional gravity. In particular, we impose strong constraints using the torsional (teleparallel) formulation of gravity in which the…